After cleansing your skin, apply a sufficient amount of serum to your face by massaging it. Wait until it is absorbed by the skin. Skin care products containing ethyl ascorbic acid can be used twice a day. We recommend applying it to clean skin morning and night. Ethyl ascorbic acid is highly compatible with other components. In fact, vitamin C; It is recommended to use it in combination with exfoliating acids and alternative antioxidants such as retinol and niacinamide.