Steps to use sunscreen effectively.

This article was taken from (https://www.allure.com/story/does-sunscreen-expire)

1. Use enough sunscreen.

"One ounce — about a shot glass-size — is needed for the face and body," says Marchbein. If you're covered below the neck and just need to apply SPF to your face, use a teaspoon, she says. "The majority of cream sunscreens are three ounces, whereas sprays are often four ounces, so you are applying a third to a quarter of the bottle every two hours," she says.

2. Reapply religiously.

"Reapply your sunscreen every two hours," stresses Gilbert. "If you're wearing makeup, a powdered sunscreen can make that a less-daunting task. I like the Colorescience Sunforgettable Brush-On Sunscreen SPF 50. It allows you to layer added protection on top of your existing makeup."

3. Be proactive.

Adding antioxidants to your skin-care routine can help protect you from sun damage, says Gilbert. "Vitamin C is a potent antioxidant that can not only strengthen your skin but also reverse some of the pigmentation caused by UV exposure," she says. "I like Vichy LiftActiv Vitamin C serum because it packs a punch at an affordable price point."

4. Have a backup method.

"Don't forget that sunscreen alone may not be enough to fully protect you from the sun," Gilbert says. "There are a ton of cute hats out there, as well as SPF workout gear, so no excuses, people!"

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