Prevention is the key when it comes to blisters. Take precautions to avoid chafing if you are going to be doing a lot of physical activity.
If you do end up with a blister try these tips from the American Academy of Dermatology to help:
1. Use padding to protect the blister and then cover the padding with a bandage.
2. Try to avoid popping or draining the blister—it could cause an infection.
3. If the blister is very large and painful and you must drain it sterilize a small needle using rubbing alcohol and then use the needle to carefully pierce one edge of the blister to allow the fluid to begin to drain. Once the drainage has stopped wash the area with soap and water and put petroleum jelly on it.
4. Watch for signs of an infection such as redness, pus, increased pain or swelling. If you do notice these signs see your doctor.