Most people know to be mindful of skin -- even tan skin -- that's exposed to the sun, but they don't worry as much about the skin that's covered. After all, clothing can protect areas that can't be covered by sunscreen, such as your scalp. A wide-brimmed hat can provide protection to face and neck. Sunglasses will protect parts of your face and eyes, particularly wraparound sunglasses. However, it is possible for UV rays to sneak through your clothes and accessories.
It's also possible to purchase clothing designed to provide additional protection against UV rays. Clothing that comes with an Ultraviolet Protection Factor (UPF) is rated based on the amount of protection it provides, so a UPF of 20 means that the item of clothing allows 1/20th of UV rays to get through.
Besides specially designed high-UPF clothing, there are certain types of regular clothing that provide more protection than others. For example, a plain white t-shirt may have a UPF of 7, while a dark shirt made out of a thickly woven fabric could have a UPF that's well over 1,000 [source: Skin Cancer Foundation]. Clothes lose some protection when they're wet or worn out, but there are also laundry detergent additives that you can buy to literally wash extra protection into your garments.