Slide a piece of extra Velcro across the surface of the Velcro with hair and debris trapped in it. Repeat several times to remove the debris.
Lie a piece of duct tape over the Velcro and press down on the tape to flatten it down. Pull up the tape. The hair and debris should come out with the tape.
Brush the Velcro with a hair brush in multiple directions to remove the hair and debris.
Comb the Velcro with a comb in multiple directions to remove the hair and debris.
Use tweezers to grasp the hair, and other debris and pull it out of the Velcro. This process is time-consuming, but may be the only way to remove stubborn hair and other debris stuck in the Velcro.