Sweatbands are an effective way to keep sweat away from your grip.
Seasoned tennis players usually develop calluses on their hands because of the repeated gripping action on their rackets during play. If you've been away from the game for a while, or you're new to tennis, your hands may develop blisters at first. Improper grip size and sweat are two of the biggest causes for those painful, sensitive sores. Of course calluses can get irritated and form blisters as well, so blister prevention is important no matter your playing level.
Proper Grip Size
If your racket twists and turns in your hand because it's either too large or too small, you will most likely develop painful blisters, notes the USTA. Make sure you are playing with the proper grip size by measuring from the middle crease in your palm to the tip of your ring finger with a foot ruler. That number is your proper grip size. Ask a tennis pro to take a look at your grip to make sure you're holding your racket in the proper way as well. If you hold the grip too low toward the butt of the racket, this can cause blisters.
Overgrips and Gloves
Most major tennis racket manufacturers make a product called overgrip. This is a tape that you wrap around your grip and has a sort of tacky or slightly sticky feel, which helps you get a nice tight grip on your racket, according to the USTA. Some players use gloves to protect themselves from blisters -- usually golf or racketball gloves -- which have the added bonus of absorbing sweat as well.
Keep Sweat at Bay
Moisture that makes you lose grip on the racket contributes to the formation of blisters. Wearing wrist sweatbands are a good way to keep the sweat from dripping down onto your grip. During changeovers, remember to thoroughly wipe down your body and grip to keep things as dry as possible.
If you already have a blister, it's important to keep it covered and free from further friction, according to MayoClinic.com. Carefully wash the blister, trying not to break the skin, and then cover it with a bandage. If you must continue playing tennis, consider wearing a glove to cover the bandage.