Originally posted by: Injury
Cut a small doughnut shaped piece of foam and tape it over the blister. You can also use a moleskin bandage, but the average person doesn't have those sitting around.
Don't pop it unless it is excessively swollen, turning odd colors, or appears to be filling with blood.
If you must run on the foot or walk long distances or something, it might be a better idea to use a pin, douse it in a disinfectant, and make the smallest hole possible, and press the fluid out. No matter what, do NOT tear off the skin. Let that fall off on its own. Avoid doing this if at all possible though.
It's not just that the skin is very sensetive, it's that it has NO protection from germs and bacteria. The feet are a breeding grounds for both of these.
Make sure you wear clean socks and change them in the middle of the day if your feet sweat.
If you know anything about the the cycle by which skin falls off and replaces itself, then you will know that your body has about a 3 day cycle for replacing skin. If the blister got through only a couple layers of skin, then baby it and you'll be fine in about 6-9 days.
If it's a reaaal bad blister, it may take up to two weeks before it feels better, but it's even more important to keep the skin on there.
<--(Boy scout.)