CB Expert Advice: Apply in the morning to clean, dry skin over the face and neck, using fingertips or a cotton pad.For maximum effectiveness, apply the Intensive Resurfacing Serum in the evening. Avoid contact with eyes and mucous membranes. Do not use on sensitive or irritated skin. In case of irritation, rinse with water, stop using the product. This product contains AHAs; it can make skin more sensitive to the sun. Use sunscreen during use and continue at least one week after the end of treatment.