In the backcountry permit office we insist that there is NO bad trip to be had here in Glacier National Park. With the right attitude and flexible itinerary options, you come into the permit office, get a permit, enjoy the Backcountry Safety Video and hit the trail. You're out there having a wonderful time in nature. Then somewhere along that same awesome trail some spots on your feet get warm. Then those hotspots turn into blisters. Then that awesome trip starts to feel a little less amazing.
Let me begin with a personal story. I, Ranger Carol, was on a backpacking trip last year when the sole of my boot came loose, making my waterproof boots a little like a sieve. I did make it back to the trailhead with the help of some duct tape without losing my sole. After failed attempts at fixing the problem via glue, I bought a new pair of boots–the same brand and size as my much-adored previous boots that I'd had for 8 years.
New boots. I understand it usually takes awhile for feet and boots to decide to get along. I took my new boots on small trips, trying to convince them to reshape to my feet, which are not the same shape as factory-made feet. This is my first tip for avoiding blistered, angry feet: break-in your new hiking boots before taking them on a long trip.
Back to the story, soon it was time for a longer trip with an overnight pack–a night at Gunsight Lake's backcountry campground. Long story, short: I got hotspots on my heels which I ignored, which soon became large blisters. But I had broken those boots in! And they were supposed to be like my old boots.
A year later (and several hundred miles later) I can tell you that those same boots and I are still not getting along. I currently have heel blisters from a 20 mile patrol I took this week in those same boots…Second tip, find boots that fit your feet. Maybe if they're not that comfortable to begin with, maybe they're never going to be comfortable. And maybe rangers should learn to let things (like bad boots) go. Boots should not be loose; your foot shouldn't slide back and forth in the boot when you walk. Tie your boots well. They also shouldn't be too tight causing toes to squeeze together uncomfortably or cutting off circulation if your feet swell.
On a similar note, choose good socks! Cotton socks often keep moisture around, which turns into a wonderful environment for blisters to grow in. Sock liners and wool socks will help keep your feet drier.
But there is another thing I could have done, could do, have done before to alleviate this pain until I accept the inevitable reality of needing good-fitting boots. I usually carry one or both of these things: mole skin and very tacky, flexible medical tape. As soon as a hotspot appears, take a break! Take off the shoes and create a barrier between the boot and your foot. A layer of mole skin or medical tape between the foot and the boot takes the friction away from your foot. When I take a break as soon as the heat starts and do this, I often completely avoid blisters. Also sometimes a small little rock or grit may be causing the discomfort. Stopping and removing it will take away the problem.
Sometimes perfectly good boots that have been great for hundreds of miles turn on you. Maybe your ankle just gets tired or maybe the incline of the trail is different from what you've been doing lately. Sometimes a perfectly good boot loses its sole. Sometimes you forget to put your sweaty boots in your tent and a marmot eats them (do not do this!). Be prepared; bring something to fix gear failures like duct tape and cording. Also take care of your boots. Things like mud can eventually dry out and deteriorate them.
Unfortunately I'm not very qualified to tell you what to do if it's too late and you already have blisters. I am not a doctor and when in doubt (when infection is present) perhaps it's best to see a real doctor. I do know that you shouldn't puncture the blister unless it's painful to walk on. If it is already punctured, keeping it clean is essential.
Prevention (and not being too stubborn to admit what the real problem might be) is the real cure to this problem! Walk it off out there, backpackers, but without blisters.