Undercutting Hair

Hair with undercutting
Q: How do you undercut medium length hair so it curls under?
A: The principles behind undercutting are the same regardless of the length of the finished hairstyle. The hair is cut so that the outer layers of hair are left slightly longer than the layers that lie closer to the scalp, which encourages the hair to curve toward the shorter lengths.
The easiest way to accomplish this is to section the hair and work with small increments left hanging down as you cut it. Each subsequent increment should be cut just slightly longer than the previous increment. Be sure to use no tension on the hair to prevent pulling the hair and stretching it. If the hair is stretched, then the cut will be uneven and the finished results will not be as desired.
You should also pay close attention to the hair's natural wave pattern, and when possible, use the hair's own wave to emphasize the under-curl. At the very least, you should avoid trying to create a curl under effect against the hair's natural wave.
Photo: Nebojsa Markovic/Shutterstock
See also:
What are undershave and undercut haircuts?
How can I define the double cut and is it different than the undercut?
Can you give me instructions on how to cut hair to make it curve under rather than flip up?
Please tell me how to get a cut in which hair curves inward up until the ears.