(This page will be about questions that barbers email me about. So it will grow over time. Enjoy:)
SHOULD YOU CUT WITH OR AGAINST THE GRAIN?
Depending on the customer as well as the hair texture. Some customers will have a fit if you cut their hair against the grain. Some customers don’t care. You as the professional sometimes have to make the decision in order to get the best results. But ultimately the customer will have the final say.
In my experience, very thick, wavy, curly hair, would have to be cut with shears until it is shorter than about 1 inch. Below 1 inch, you can cut with the grain up until about half an inch. Below half an inch, I would suggest going against the grain.
Hair with swirls in it can be cut with the grain while it is longer than about an inch. Once you cut below an inch, you can possibly gap the hair. Swirls are tricky. You either have to cut swirls with shears or just cut the swirl only against the grain.
For example: If you cut someones hair with the grain and you are using a #1 guard, everything will be fine until you get to the front of the haircut and the right side of the customers head has a swirl. Continue to cut the hair cut with the grain and leave the swirl for last.
Once you have finished cutting the top with the #1 guard and all you have left is the swirl, take a larger guard and cut the swirl area only against the grain. If you are using a pair of regular clippers, always adjust them wide open and work the adjustments closer and closer until you achieve the result that you desire.
If you are using a Oster 111 and you have used a 1 blade for the length on top, now you can use a 1 1/2 or 2 blade to cut the swirl against the grain.
These methods are good if a customer is trying to keep his hair dark or thick on top. Once a customers hair goes shorter than a #1 guard, then I suggest cutting it against the grain in order to get an even toned haircut.
Pictures of haircuts with a #1 metal guard with the grain or Andis Masters adjusted wide open without a guard and with the grain.