After cleansing in the evening, massage a small amount of Crystal Retinal across the face, neck and and décolletage. Allow to absorb before applying your moisturiser. Crystal Retinal application should be phased in gradually, and only use in the evening. Use twice a week for the first 2 weeks, every other night for the next 2 weeks, then every night. Always wear sunscreen the following morning while using this product, and for 1 week after. Consult a doctor if breastfeeding or pregnant.