After a long, cold winter, there's nothing better than feeling the warm summer sun on your skin. And while the warmth is nice, remember that the rays are not. Ultraviolet A and ultraviolet B rays (UVA and UVB rays) damage your skin. This leads to early wrinkles, skin cancer and other skin problems. Being in the sun often over time, even if you don't burn, can lead to skin cancer. A tan, no matter how nice it looks, is a sign that your skin has been damaged.

The key to protecting your skin is to avoid being in the sun, especially from 11 a.m. to 3 p.m., when the sun's rays are the strongest. If you're going to be in the sun for any length of time, use sunscreens with a sun protection factor (SPF) of 15 or more. Put the sunscreen everywhere the sun's rays might touch you, including your ears, the back of your neck and bald areas of your scalp. Put more on every hour if you're sweating or swimming.

You can also wear clothes made from tight-woven cloth so the sun's rays can't get through to your skin, and stay in the shade when you can. Wear a wide-brimmed hat to protect your face, neck and ears. Wear sunglasses to protect your eyes from the sun. Choose sunglasses that block both UVA and UVB rays.

Remember that clouds and water won't protect you — 60% to 80% of the sun's rays can get through clouds and can reach swimmers at least one foot below the surface of the water. The sun's rays can also reflect off of water, snow and white sand.

Also, don't use tanning salons. Tanning booths damage your skin just like real sunlight does.

To check yourself for skin cancer, stand in front of a full-length mirror and use a hand-held mirror to check every inch of your skin, including the bottoms of your feet and the top of your head. Have someone help you check the top of your head. Try using a blow-dryer set on low speed to move your hair out of the way.

Look for any changes in a mole or the appearance of a new mole. Any moles that appear after you turn age 30 should be watched carefully and shown to your doctor.

The "ABCDE" rule can help you look for signs of skin cancer. When you look at moles on your skin, look for the following:

A for asymmetry: A mole that, when divided in half, doesn't look the same on both sides

B for border: A mole with edges that are blurry or jagged

C for color: Changes in the color of a mole, including darkening, spread of color, loss of color, or the appearance of multiple colors such as blue, red, white, pink, purple or gray

D for diameter: A mole larger than 1/4 inch in diameter (about the size of a pencil eraser)

E for elevation: A mole that is raised above the skin and has a rough surface