HANSKIN Vitamin A Glow Retinol Serum is used in the evening, on clean, dry skin, after cleansing and before moisturizer. Start with 2 to 3 nights per week, applying 1 to 2 pumps over the entire face while avoiding the eye and lip areas, then gradually increase the frequency if your skin tolerates it well. Remember to moisturize thoroughly afterward and apply generous sunscreen every morning, which is essential with retinol to keep your skin radiant and protected.