**Detailed Explanation of BOB Haircut**
Firstly, when you see the triangle below the occipital bone, it represents the final cutting result after trimming. Before that, there should be a downward-to-side trend. The first section is located in a small hollow below the occipital bone. From this hollow, you partition lines towards both sides [A]. At this point, you will notice that the diagonal partitions are relatively sharp and stiff. As we move upwards, it gradually becomes more curved. When pulling out the first section for trimming, we need to make four cuts. Why? Because after finishing the entire section, there will still be an arc here. This arc corresponds to the most prominent point of the head shape. If you make it too stiff without creating a rounded line (as taught in hair schools like Huai'an Beauty School [http://www.haainisi.org]), this part is the most concave part of the skull, so we need sufficient hair volume to naturally fill in this concavity. Sometimes, it may slightly bulge out, but don't worry; it won't feel overly tight upward. No matter how thick you cut, it will always have a slight inward curve due to its 360-degree rotation, making it look beautiful. (Many stylists often cut in one stroke without considering the skull structure.) In the second step of partitioning, the point is slightly higher. Make the first cut at this position, then re-lift the hair section. By re-lifting the hair section (as taught by Huai'an Beauty School [http://www.haainisi.org]), you are allowing more length to be retained. Then, pull and cut again: the first cut is shorter, the second longer, the third even longer, and the fourth cut tapers inward. On a real human head, six cuts can be made for a softer arc, while four cuts remain relatively stiff. Since each person’s cutting line length varies, your proportions may also change.
Similarly, when moving from the second section to the third, pull out the hair section. You will notice that the middle part is longer, and the sides are shorter. This is after trimming; before trimming, the lengths vary. However, the clear concept in your mind should be expanding the circular triangle. Above the occipital bone, it expands, while now it contracts (Huai'an Hairdressing Training [http://www.haainisi.org]). Ensure that the cutting line is parallel to the partition line. For you, this is the parallel line. You will find that the hand position gradually moves from high to low, downward. One cut, two cuts, three cuts, four cuts. When making the fifth cut, we align our hand bones tightly with the person's body. Then, through finger adjustments, ensure the roundness of the skirt-like movement. After finishing the cut, directly trim the guiding lines from the side. When reaching the third section, there will already be side-operating guiding lines. The advantage of finishing this way is that many times, even Vidal Sassoon wouldn’t teach this method because they fear students might get confused. So why isn’t the hand position parallel to the cutting line and partition line at the final stage? Why? Regarding this hairstyle, it’s about the motion of styling. Since you will still need to cut these lines later, if you don’t perform this action, the lines after cutting will appear too heavy. When using thinning scissors, it might look nice, but it could also create disconnected layers. At this moment, use a finger adjustment to handle it. The resulting curve will feel soft. To achieve a round shape, the only thing forcing us to do this is shortening the cutting line. This is the only way we can accomplish it. When the cutting line is too long, no one can achieve it. Why? Because angles will be produced, which won’t give a smooth feeling. The purpose of making a round shape is to adapt to different head sizes. We hope it produces various circular shapes, slimming according to the era. The round shape makes the face look slimmer and more beautiful. After finishing the third section, move upward to the fourth section, which is the key. In the fourth section partition, you will notice that this area reaches the occipital bone position, while our turning line is still below the occipital bone. You need to clearly understand that your hand position operates from high to low. Also, remember that your hand above the occipital bone at this position is not just a point, but a two-centimeter-long line. When cutting the middle part, our hands are level for two cuts. Then, gradually tilt and release using fingers. The purpose of releasing is to create a round shape. Through different angles, exercise your hand control over the hair sections. This is the round shape you cut, which appears smoother. The hair section partition moves from high to low, and your hand also releases from high to low. The only difference is that the first cut is parallel, and the second cut is downward—these remain unchanged.
The third and fourth sections both require hand rotation. Should the fifth section rotate as well? Definitely yes. Why? Because you already have guiding lines. When these guiding lines drop down, they are not as large or strong as the third section, but still have a slight inward curve. Gradually partition upward. When we reach around the sixth section, we have already extended from the back toward the side. Remember, the first partition line must be thick, and the side is One Length. The guiding line on the side has some changes here, but it still retains a diagonal arc, gradually becoming One Length—it is definitely not flat. When we reach eight to nine sections, it gradually becomes a parallel line. On the head, it forms a [U]-shaped partition, all finding natural falling points. There are no straight lines. Books show straight lines because books are flat, but heads are three-dimensional geometry. This head shape has a weakness: pointed heads are less suitable, which should be noted.
b. **Round** – Gradually accumulate weight following the head shape. The explanation of "Round" is circular. The head shape is higher in front and lower in back. In this technique, the most representative work is Shake. Below, I will explain the detailed haircut process of Shake, which is a necessary technique in the classic Vidal Sassoon course. The accumulation of rounds is crucial in knowing the 0-degree direction around the hairline. From 0 degrees to 90 degrees, it slowly changes, following the head shape on a cylinder, finally dropping down to accumulate.
Shake begins by establishing the outer line shape, following the head shape to build the internal structure, i.e., a three-dimensional space. When each section is finished, it forms a three-dimensional circle. Looking at the entire head, it appears as a circle, a circle from top to bottom, and a circle when swaying left and right. The outer line composition is also a circle (outer ring line). What kind of circle? An ellipse. Not equal length. The biggest difficulty for everyone is the ellipse. The only thing that can help you remember is the position of the occipital bone. Every hair section at the occipital bone position is the longest strand. From it upward forms a circle, and downward forms another circle. At this time, you will find that the hairline and ear hairline on both sides are relatively short, while the middle expands in length.
Assume there is a fruit bowl on the table, a pile of orange segments, possibly from five oranges. You will notice that the ends are sharp, and the middle is narrow. In this hairstyle, it resembles a stretched-out watermelon from Xinjiang, forming an elliptical shape. The most important part of this ellipse is the occipital bone. When trimming the first section, you will find that all the hair is at 0 degrees because after cutting, no further changes are needed. When cutting these strands, we must reach the natural falling point, and our cutting line must be parallel to the partition line. The result of being parallel is that the cut will definitely have an arched circular direction, shorter in front and longer in back, with no gaps. Many times, we fail because after cutting this hairstyle, you will find missing parts for various reasons, such as the hand not lifting properly or slightly moving forward. After cutting, you may ask the teacher why it moved forward and became longer. You will find that the connection of lengths differs from direct cutting. It’s not about how beautiful the haircut looks but rather the high control over the circular direction after cutting, which will slow you down. The length your scissors span should become a single point, working point by point for the best results. Another aspect is when cutting the outer contour, your hand position should lift and rotate, slightly detaching your hand bones from the lifted hair section. Different hand controls will give different results. The second section has an elevation of approximately 30 degrees, meaning there is a 30-degree difference between the second and first sections. When dropped, it is not a cover but light. The second section at 30 degrees, 40 degrees, 50 degrees, 60 degrees, 70 degrees, 80 degrees, and 90 degrees—where is 90 degrees? At the occipital bone position. And for each section of hair, you will find that the third section is slightly higher, the fourth section slightly lower, and the fifth, sixth, and seventh sections almost on the same horizontal line. You will notice the occipital bone and the removal of weight above it when cutting into a circle. When you cut open, the two together form a pile. Below is a pile, and above is the removal of weight, meaning the circle follows the head shape, cutting into a circle. The difficulty lies in when we cut to the third section, at this point, there is no guiding line below the outer line. Indeed, there is no guiding line; its guiding line is the drop point of the second section. The guiding line of the third section is also the guiding line of the outer line, requiring you to find that circle yourself. Therefore, when connecting internally, after dropping, it forms the continuation of the outer line circle. So, you must consider the length of the last strand of hair and the previous lifting angle. Thus, every strand of hair will reveal this transformation while fixing the up-down and left-right directions to form that circle from 0° to 90° and beyond, making it very challenging. When trimming the fourth section, continuing to the fifth, sixth, and seventh sections, all are opened. Why? Each hair section exists at 0 degrees because it needs to connect the overall outer circular feel. Additionally, many people fail to bring the last section inward.
Your arc becomes a bend, pausing. It requires a higher level of control to connect the fifth section upward, cutting three to five strokes. The next position is not the fourth section but the fifth section. Rotate your hand inward to form a pocketed circle. A three-dimensional object requires body positioning. The sixth and seventh sections continue upward, gradually closing to form a circular sensation. Cutting this head shape with nine sections is easier. The other half is the same as this half, using the already trimmed side as a guiding line, cross-checking with a G-BOB partition.
C. **Square** - Gradually accumulate weight, with internal angles, shorter below and longer above (1-89°)
Square refers to the pulled-up surface. The purpose of making it square is to retain the length on both sides, where the head shape is curved, commonly used at the back of the head. The lower hair pushes the longer hair, forming a full contour.
3. **Layer** - Remove weight??? Layer means layers, with angles ranging from 90° to 90° or more.
a. Classic/Square - Remove weight from all four surfaces of the head (top, back, right, and left).
Classic means classic, Square means square, with an angle of 90°.
In this technique, the classic Square Layer BOB, explained in essential training courses, must be practiced.
Simply pull all the hair toward the back, allowing this hairstyle to achieve weight accumulation and removal. The square removes weight, telling you that length can alter visual perception. First, divide the head into a One Length Bob partition. There are several major partitions simplified. The first partition still resembles a bridge-shaped arc, cutting the desired arc. This arc will be smaller because the weight above will soon be removed. Dividing into A, B, and C zones, Zone A extends slightly above the occipital bone, pulling completely different skeletal structures to the same surface. The position of the hairline in Zone A's trimming may be hard to reach. How to choose the length of the first strand of hair behind is the key to the entire hairstyle, i.e., the fusion point of Zones B and C (the corner line position). When it naturally falls on the occipital bone, forming an arc, if this strand is cut too short, it becomes flat, sticking close without a full feel. Therefore, it must be lifted at 90°. When it naturally falls, it forms a fullness, which changes when done on a client, combining elements. Here is a pure technique, making squares involves Overdirection, i.e., 2”1, 3”2, 4”3, 5”4, pulling the fifth section's hair to the back, retaining the outer line length. The fifth section's hairline is quite high. Pulling too much or too little will change the outer line length. Zone B has side volume, referring to the volume before the corner line. All the side hair is pulled to the back, retaining the BOB outer line. The purpose of making a square is that whoever pulls the furthest limits the retention of its length, horizontally and vertically, practicing control. The thumb always points in the direction you want to cut. Zone C will have the front hemisphere and the rear hemisphere. The spinning part is the rear portion, having many [7]s or [corners]. If connected, good effects can be achieved. Letting out the hair volume from the spin, the [7] partition is irregular, following the hair flow direction, pulling toward [A] point, not too thick, with a slight lift, forming a side arc, having a one-finger lift, falling to form a full occipital bone.
B. **Round** - Circular. Each partition maintains the same length and proportion, not arbitrarily increasing or decreasing internal weight. Must lift at 90°, equal length, each strand the same length, considering the differences in bone structure, the direction of each cut is also different, 90° is vertical pulling.
C. **Concave** - Concave, reverse curve. The head shape is inwardly curved, which is the opposite direction, also referring to the surface, a curve opposite to the natural head shape. Short in the middle, long on both sides. The purpose of this technique is to maximally retain the outer line greater than 90°, usable at any position on the head, colloquially triangular weight removal.
4. **Combination** - Combining several or all factors from the above three haircut techniques, embodying beauty in hairstyles, impossible to use just one technique. Based on bone structure, create different hairstyles, lines, structures, and geometric shapes, which become the three creative and inspirational elements of Vidal Sassoon, three techniques, nine variations.
**Graduation** - Accumulating weight. Two reasons for using Graduation:
1. Changing volume.
2. Movement - Changing dynamics.
Accumulating weight occurs at angles below 89°, with choices expanding. Hairstyle manifestation includes dynamics, volume, and texture. Three ways to create Graduation T.O.E.
T: Tension applied to the hair (any force) tension always exists.
Tension determines the primary characteristics of line personality. Tension determines whether the outer hair is clean. Tension should ideally be minimal and uniform. Use a wide-tooth comb to brush the hair. Small-tooth combs differ in pressure, varying dryness and elasticity, producing different results. But tension always exists. Hair effect differs, hair elasticity differs, no standard exists. The size of tension has no standard and cannot be measured, only known to oneself.
O: Overdirection - Pulling hair away from the natural falling direction to create dynamics.
A strand of hair has four directions. O controls the geometric shape of the horizontal plane, simply left-right issues. 2→1, 3→2, 4→3 forms a square surface. 2→1, 3→1, 4→1 forms a triangular surface. Kinetics has short pushing long.
E: Elevcotion-Lift - Used to create volume.
Controls the geometric shape of the hairstyle's vertical plane. Up-down space issues, also determining the length of the outer line.
The higher the angle, the lighter the volume; the smaller the angle, the heavier the volume. 45 degrees is commonly used in accumulating weight, though not the most standard. 45 degrees is easy to find. The hairline hair also determines the length of the outer line.
Key Points of Head Shape Diagram
Major Section - Main partitions indicated by thick lines. Three types: horizontal, vertical, and diagonal.
Horizontal Partition: Helps establish weight.
Vertical Partition: Removes weight.
Diagonal Partition: Helps establish hairstyles with round momentum.
Haircut partitions should be parallel to the final hairstyle's external shape, with moderate sizes, controlling hair and capturing guiding lines. The size of the partition depends on the haircutting technique used.
Section/ Subsection ——
Cutting Line ——
Direction of pulling hair —— Using Overdirection
Hair pulled straight out ●
Hairline ~~~~ Determines the length of the outer line
Scissor over comb —— Rubbing slope
Vidal Sassoon's three techniques and nine variations in circles, squares, and triangles
Only Vidal Sassoon's classics can change hairstylists; Vidal Sassoon's classics are the foundation for hairstylists to stand on.
In the overview of Vidal Sassoon techniques, there are three parts: the first One Length is the 0-degree natural fall achieved by the outer line.
Horizontally, it is square, front-shorter-back-longer following the head shape is round, finding each natural fall, triangle is front-longer-back-shorter. Their boundary is at the corner line behind the ears. In accumulating weight, it ranges from 1 to 89 degrees. Square is pulling to one surface, short in the middle and long on both sides, with internal angles. Making square retains the length on both sides, following the head shape.
Triangle is the 1965 GBOB requiring 45 degrees below the occipital bone, pulling above the occipital bone toward the occipital bone.
The third technique is LAYER, removing the classic square. Four surfaces can be removed, or all hair can be pulled toward any one surface at 90 degrees. The round technique requires equal 90-degree treatment. Concave means a concave surface, short in the middle and long on both sides, a reverse curve. The technique of extremely retaining the outer line, finally, is the kinetics T O E, where T is tension,
O is the geometric shape of the horizontal space, E is the geometric shape of the vertical space.
Vidal Sassoon's classic accumulation G BOB can be done this way.
G BOB Similarly, when moving from the second section to the third, pulling out the hair section, you will see that the middle part is longer, and the sides are shorter. This is after trimming; before trimming, the lengths vary. However, the clear concept in your mind should be expanding the circular triangle. Above the occipital bone, it expands, and now it contracts. Achieve parallel cutting lines and partition lines. Regarding this, it is your parallel line. You will find that the hand position gradually moves from high to low, downward. One cut, two cuts, three cuts, four cuts. When making the fifth cut, we align our hand bones tightly with the person's body. Then, through finger adjustments, ensure the roundness of the skirt-like movement. After finishing the cut, directly trim the guiding lines from the side. When reaching the third section, there will already be side-operating guiding lines. The advantage of finishing this way is that many times, even Vidal Sassoon wouldn’t teach this method because they fear students might get confused. So why isn’t the hand position parallel to the cutting line and partition line at the final stage? Why? Regarding this hairstyle, it’s about the motion of styling. Since you will still need to cut these lines later, if you don’t perform this action, the lines after cutting will appear too heavy. When using thinning scissors, it might look nice, but it could also create disconnected layers. At this moment, use a finger adjustment to handle it. The resulting curve will feel soft. To achieve a round shape, the only thing forcing us to do this is shortening the cutting line. This is the only way we can accomplish it. When the cutting line is too long, no one can achieve it. Why? Because angles will be produced, which won’t give a smooth feeling. The purpose of making a round shape is to adapt to different head sizes. We hope it produces various circular shapes, slimming according to the era. The round shape makes the face look slimmer and more beautiful. After finishing the third section, move upward to the fourth section, which is the key. In the fourth section partition, you will notice that this area reaches the occipital bone position, while our turning line is still below the occipital bone. You need to clearly understand that