Cristaux Retinol Serum 30ml

Apply retinol once a week in a thin layer to your entire face (be careful not to get it in your mouth, nose and eyes) at first to see how your skin reacts. Then gradually work up to every other day or three times a week. Another key tip for using retinol products is to incorporate it into your nighttime skincare routine only, as it makes skin more sensitive to sunlight

“should use a dose that's about the size of a pea.”