1) Make A-line at nape region. And cut guideline at desired length at 0 degree.
2) Now we will start from one side, complete it and then move over to the other side of head.
3) Now take a diagonal section which has some hair from the guideline. Take this section over the clients shoulder. And cut it at 0 degree over the shoulder.
4) Take similar diagonal sections and keep them cutting over the clients shoulder and cut them at 0 degree. Note that all the sections would be cut at the exact same place over the clients shoulder.
5) Move over to the other side and cut hair similarly on the other side.
6) Once all the hair is done. Your haircut is done. When you comb back all the hair, you should be able to see a perfect U shaped hair.
7) Your haircut is done. Now for Checking, Keep all the hair from client’s one shoulder to other shoulder in a proper U shape.
8) Now take big sections between your fingers and slide down from the top till the end. And check for any stray strands of hair. Cut if any extra strands coming out.