In this video you can see how to perform a Development Test Curl.br •This test is performed to see if the development curl in a perm is correctbr •Unwind the curler about 1 turn.br •Push the hair towards the scalp.br •The hair should rest into an "S" shape.br •When the "S" shape is the correct size as the size of the curler the processing is finished.br Hope you have found this video useful.