1 Clean the blister area with soap and water.
2 If the blister is not too swollen or painful, skip to Step 4. Otherwise, use a match flame to sterilize a pin or the tip of the sharpest blade on your pocketknife, then carefully cut a small slit at the bottom of the blister to drain the fluid. Leave the skin flap in place to protect the wound and speed healing.
3 Apply antiseptic ointment or a small circle of a nonadhering sterile dressing, such as Spenco 2nd Skin, directly on the blister.
4 Cut a doughnut-shaped piece of moleskin with a hole that's slightly larger than the blister. Place it over the blister and sterile dressing to create a pressure-free pocket for the sore. Cover the entire doughnut with a second piece of moleskin.
5 Secure the moleskin patch in place with medical tape. In a pinch, duct tape will do the job. For heel blisters, run tape strips along the sides of your foot toward the toes, then secure the ends with a few loops run around the instep.
6 Promote healing by keeping the blister moist with ointment or sterile dressing.