Blisters are the most common reason hikers cut trips short, and they are almost entirely preventable. A blister forms when repeated friction separates layers of skin and fluid fills the gap — and once it forms, every step hurts. The good news is that prevention is a system, not a single trick: it starts with your shoes, continues with your socks, and finishes with how you respond to the first sign of trouble. Get the system right and your feet will carry you for hundreds of miles without a single blister.

Most blisters come from shoes that do not fit, not from shoes that are cheap. Your hiking shoes should have a thumb's width of space in front of your longest toe, because feet swell during the day and slide forward on descents. Try shoes on in the afternoon when your feet are at their largest, and wear the socks you will hike in. Trail runners have become the default for long-distance hikers because they are light, dry fast, and need almost no break-in — but they only work if the fit is right. Whatever you wear, break it in with at least 30 miles of training walks before a big trip, including hills, because new shoes on day one of a thru-hike is a classic blister recipe.

Socks are the layer between your foot and your shoe, and they do more work than most hikers realise. Merino wool socks wick moisture, cushion the foot, and stay warm when damp, which is why they dominate the trail. Change into a dry pair at lunch on hot days — carrying two pairs and rotating them is worth the few extra ounces. Some hikers wear thin liner socks under their main socks to reduce friction, and this helps people who are prone to blisters between the toes. Avoid cotton socks entirely: they hold sweat, stay wet, and turn soft skin into blister-prone skin within hours.

The moment you feel a hot spot — that warm, tender patch that comes before a blister — stop and deal with it immediately. Five minutes of attention now saves days of pain later. Cover the spot with Leukotape or moleskin, smoothing it flat so it does not bunch up and create a new friction point. Anti-friction balm or petroleum jelly on known trouble areas before you start walking reduces rubbing all day. Keep your tape and a small pair of scissors in an accessible pocket, not buried at the bottom of your pack, because you will not stop to dig for them when you are trying to make miles.

What you do at camp matters as much as what you do on the trail. Take your shoes and socks off as soon as you stop, let your feet air out, and wash them with water and a little soap if you can. Dry feet overnight recover far better than feet kept in damp socks, so always sleep in a clean, dry pair. Air your insoles and shoes out too — stuffing them with dry clothing or hanging them helps them dry by morning. Check your feet each night for redness, maceration between the toes, or early blisters, and tape anything suspicious before you sleep so it is protected for the next day.

Even with good prevention, blisters sometimes appear — usually from a new shoe, a river crossing, or an unexpectedly long day. Do not pop a blister unless it is large, painful, and likely to burst on its own; intact skin protects against infection. If you must drain one, clean the area, sterilise a needle, make a small hole at the edge, press the fluid out gently, and cover it with a sterile dressing and tape. Watch for signs of infection — spreading redness, warmth, or pus — and take them seriously in the backcountry. The best blister treatment is still prevention, so after every blister, ask what went wrong: fit, moisture, or a missed hot spot, and fix it before your next trip.