Wash with products for Caucasian hair (I recommend Tresseme). Aim to condition the hair for 1 hour after washing it, this will help to nourish the cuticles. Ideally let the hair air dry as oppose to using a blow dryer. If you wear the wig regularly wash it at least once a month. Minimise using hot tools to prevent damage If you choose not to remove your wig at night, use a satin scarf of bonnet to ensure it's longevity.
