Start low: Start with 0.25% until your skin builds tolerance. Apply at night on dry skin & apply moisturizer to minimize any potential dryness or irritation. Go slow: Start by applying it only 2x/week for a few weeks. Pay close attention to how your skin reacts; if you experience excessive dryness, redness, or irritation, scale back. Stay consistent: It is only with consistency that you will truly see the benefits. We recommend sticking to a product/ingredient for 4-8 weeks!