Using a hair spa concentrate is super easy. All you have to do is blend one bottle or capsule of hair spa concentrate with any cream bath of your choice. Next, apply the blend to towel-dried shampooed hair. Message the product on your scalp for 20 minutes, and then comb your hair and wait for another 10 minutes. Use a steamer or warm towel to wrap your hair and let the hair spa concentrate and creambath work their magic. Hair spa concentrates like L’Oréal Professionnel Hydrating Concentrate can be used both in a hair spa session or as a leave-in product.