STEP 1: GO BROAD Choose a broad-spectrum sunscreen with an SPF of at least 15. I like Neutrogena Ultra Sheer Stick with SPF 70 ($10). But remember: "The only 'safe' tan is faux from a bottle," says Joshua Zeichner, MD, assistant professor of dermatology at Mount Sinai Hospital.
STEP 2: REAPPLY YOURSELF The general rule is to apply every two hours, plus after swimming or sweating, regardless of what the label says. "Ingredients degrade and become less effective when exposed to the sun, which is why you need to reapply," Zeichner says. Don't forget your ears, neck, chest, and hands.
STEP 3: SOOTHE If, despite the best sunscreen-application intensions, you still get sunburned (or if you missed a spot), hydrate skin with a gentle moisturizer, such as CeraVe Moisturizing Cream ($15). If blisters emerge or you see no improvement, visit your dermatologist.