Do we really need to tell you how critical sunscreen is now for preventing wrinkles later? Didn't think so. But keep in mind that you can enhance the protective powers of your SPFand minimize free-radical damage that will later contribute to tiny creasesby using it along with an antioxidant serum. In the morning, first apply serum, then sunscreen. At night, says N.Y.C. dermatologist Neal Schultz, let the serum soak in before slathering any moisturizer on top.