Use the mask after shampooing, while your hair is still damp. Gently squeeze or towel out excess water first, because heavily dripping hair dilutes the product. Apply from mid-lengths to ends and avoid the eye area. If your scalp is reactive, start with a small amount and keep the mask away from the roots rather than massaging it into the scalp.
Because the product is a 946 ml format, you can afford to be generous on long or thick hair, but it is still smart to begin with a small amount and add more only if the lengths are not fully coated. Leave the mask on for a few minutes, then rinse thoroughly with warm, not hot, water. Rinsing with very hot water can make the hair feel rougher and increase frizz.
This type of mask is usually used as a deeper step in place of your regular conditioner. How often depends on how dry or damaged your hair feels; if it starts to look heavy, reduce how frequently you use it. If your skin is sensitive to cosmetic actives or fragrance, do a patch test on your inner arm before the first full use. After rinsing, continue with your usual leave-in product, detangling spray, or styling routine.