If you plan to be in the sun this summer, take common-sense precautions to protect your skin against overexposure, Northwestern Medicine says. First, choose a sunscreen that has an SPF of at least 30 and UVA and UVB protection; apply it liberally to all exposed areas of the body. Then, wait 15 minutes for the sunscreen to be fully effective before exposing yourself to direct sunlight, and reapply it periodically according to the label instructions. Note that no sunscreen is truly waterproof, however. #SummerSafetyTips