Use as the first step in a two-part system with N 3 Hair Perfector
STEP 1 : On dry hair, work No.0 into small sections by squeezing the liquid into the hair to be fully absorbed as you go.
STEP 2 : Lightly saturate hair. Hair should be damp not drenched. Leave on hair for 10 minutes. Do not rinse.
STEP 3 : Apply No.3 over the No.0, comb through and leave for at least another 10 minutes.
STEP 4 : Rinse, for best results shampoo with No.4 and condition with No.5
APPLICATION TIP: No.0 bottle should last 3-6 applications, based on hair length and density