Root should be applied once a day, directly to the scalp. Since application should be focused on the scalp, it can be used when hair is wet or dry, and should be massaged into the scalp thoroughly to help increase blood flow and stimulate follicles. Root works best when left in overnight, however, some customers choose to wash Root out after a minimum of 10-15 minutes of wear. Root is also safe to be left on the scalp all day, although we would recommend washing out after one full day of wear to avoid overcoating follicles.