One of the key missions of The Skin Cancer Foundation is to spread the “Gospel” about the importance of shielding your skin against the sun’s harmful ultraviolet rays (UVR). Spending time outdoors can be a great joy, but we want you to do it while limiting direct, unprotected exposure to UVR, which can cause everything from wrinkles to skin cancer. So follow these 10 Commandments:

1. Seek the shade: If you’re out for any length of time, find a pavilion roof or large, leafy tree to stay under. Or, carry shade with you – bring a sun umbrella.
2. Wear protective clothing: Our clothes provide varying degrees of sun protection. Loosely woven and light-colored clothes such as white T-shirts let in many damaging UV rays, while densely woven and bright- or dark-colored fabrics provide greater sun defense. Long sleeves and long pants cover more of your body, while a broad-brimmed hat helps protect your face, ears, and back of the neck.
3. Wear sunglasses: Over time, sun exposure can harm the eyes, increasing the risk of maladies from cataracts to eyelid skin cancers and conjunctival melanomas. UV-blocking sunglasses shield your eyes and surrounding skin; large lenses and wraparound styles are best.
4. Use sunscreen with an SPF of at least 15. SPF, or Sun Protection Factor, is a measure of protection against the sun’s UVB (short-wave) rays, the main cause of sunburn. However, sun damage can occur even without burning; UVA (long-wave) rays can be as harmful as UVB rays, and SPF does not measure UVA protection. So make sure the suncreen also contains chemicals such as avobenzone, Mexoryl, zinc oxide, or titanium dioxide to protect against UVA.
5. Apply sunscreen 30 minutes before sun exposure: This gives it time to fully absorb and bind to your skin.
6. Reapply every two hours, since sunscreen wears off. Also reapply immediately after swimming or sweating heavily.
7. It’s best if sun exposure takes place in early morning or late afternoon: The sun’s rays are least intense before 10 AM and after 4 PM.
8. Make sun exposure gradual. Even when you use sunscreen, some UVR gets through to your skin. Limit sun exposure to 15 minutes the first day, 30 the second, 45 the third.
9. Every year on your birthday, examine your birthday suit head to toe. To be even safer, examine yourself once a month. See a doctor if you find any unusual-looking moles: These include those that increase in size or thickness, appear after age 21, or show any changes in texture, shape or color. Certain characteristics may be warning signs of melanoma, the deadliest form of skin cancer.
10. There is no safe tan: A tan is never healthy; it results from DNA damage. When exposed to UVR, the skin’s pigment cells darken to prevent further damage. Enzymes then try to repair the damage, but these attempts are not perfect, and the unrepaired damage can produce mutations that lead to skin cancer. Stick to all these Commandments religiously, and you can enjoy your time in the sun safely.