10 Blister-Busting Tips

1. Make sure your boots fit properly and are broken in. Hiking shoes should be around one size bigger than what you normally wear.
2. Treat leather boots with saddle soap, mink oil, or a compound recommended by the manufacturer.
3. Wear sock liners (do not use cotton; instead, use a wicking fabric like polypropylene or Thermax that moves the moisture away from your skin) and heavy, well-cushioned wool socks. It is best to buy a brand made especially for hiking. 
4. If you have a habitual blister spot (the back of the heels is a common one), put a piece of medicine tape or moleskin over it before you even start walking.
5. Pay attention! If there is any rubbing or soreness, STOP! Don't wait to see if your sock will rearrange itself. It won't. Don't tough it out till lunch. You can't. Don't say: “Maybe this won't turn into a blister." If you don't stop, it will.
6. Check for the problem. Shake out socks and boots. Make sure the sock isn’t folded or creased. Make sure toenails are pared.
7. If there is any visible irritation, even if it's just a tiny red spot, treat it immediately. You can cover the irritation with medicine tape. Some people prefer moleskin or even duct tape.
8. If the hot spot is very red, or wrinkled, or if the skin has broken, treat it like a blister.
9. Keep your feet dry. Change socks if necessary. Use gaiters to keep water (and pebbles) out of your boots. In heavy rain, put adhesive tape on both heels before you start walking. Even well-broken-in feet are prone to blister in very wet weather.
10. Go easy on the trail. Every time you make a stop longer than 20 minutes do the following: remove and ventilate your shoes, remove and ventilate your socks, let your feet dry and rest.