Black Ice Professional Building Fiber Spray Applicator Step 1 Apply Hair Building Fiber Over Thinning Areas : Position bottle over your head, holding it at 45 degree angle. Gently push the rubber then spray the fibers over your hair until the thining areas are no longer visible and you are satisfied with the fullness and volume of your hair. Step 2 Pat the hair building fibers into your hair and gently blend them into your natural hair. Doing this will make the hair building fibers completely undetecable. Step 3 Use just a little bit of hair locking spray for added control. If you need to remove hair fibers from your hair, just wash the product with shampoo. It is really that easy.