Haircutting, Clipper Work, and Styling
The four decisions behind every cut
Every haircut question boils down to section, elevation, distribution, and guideline. Elevation is the angle the hair is held away from the head, and it determines where length builds: 0 degrees cuts flat and leaves weight at the perimeter, 45 degrees graduates, 90 degrees creates uniform layers, and 180 degrees produces long, shag-style layering. Distribution is where hair is directed relative to its own section - a question asking why a cut "builds weight at the perimeter" is usually testing whether you recognize low elevation plus over-direction. Tension is the third variable: wet hair stretches, so heavy tension while cutting wet shortens the finished result.
Clipper mechanics
Guard numbers run in eighths of an inch: #1 = 1/8", #2 = 1/4", #3 = 3/8", #4 = 1/2", #5 = 5/8", #6 = 3/4", #7 = 7/8", #8 = 1". Multiply the guard number by 1/8 to get the length. Fades are built from the skin upward: establish the baseline, work up through the guard sequence, blend with clipper-over-comb, then detail with a trimmer. Cross-check in the opposite direction of your original cutting lines; any ridge you find is a missed guide.
Traps
Questions swap elevation with distribution, and they like to imply texturizing shears add volume (they remove it). They also mix up shear-over-comb (shears ride the comb, softer result) with clipper-over-comb (clippers ride the comb, tighter result). Remember that a cowlick or growth pattern determines direction of styling, not a reason to cut shorter.
Rule of thumb
Before any cut, comb the hair in its natural fall and read growth patterns; then cut opposite the direction of growth where the client wants lift, and with it where the client wants the hair to lie flat and behave.