From outdoor survival guru Pat McHugh:

Some of the points to consider when buying a new pair of boots…

Your feet are your primary mode of transportation; they support your body and provide the way in and out of most wilderness areas. An uncomfortable and ill-fitting pair of boots is like having a flat tire on a car with NO spare and you are 100 miles from nowhere. The car is basically useless and if you got bad boots on, so are you.

• SHOP AFTER DARK – your feet tend to swell more at the end of the day, just like they will be when you are on the trail.
• TAKE YOUR OWN SOCKS – take the socks or combinations of socks that you will normally wear when you are on the trail with you when buying boots. This way you get the right fit.
• DON’T GET TRAPPED BY THE NUMBERS – one company’s size 10 may be another company’s size 11. Try on different sizes. Measure your feet in the store with that metal device that measures length and width and your left and right foot.
• BOOTS DON’T GET LONGER – wiggle your toes after tightly lacing up the boot. Your toes “should not” come in contact with the front of the boot. Boots will stretch in width, but they will not grow longer.
• GET A PRO- don’t buy boots that you are going to spend a long time in the field, or in wet or wintry weather from any un-knowing clerk. Get the “pro” in the store to fit you. Tell him where and how you are going to wear the boot and ask directly what would he recommend. If you buy mail order make sure they have a return policy, just in case they do not fit.
• BREAK IN – wear all boots for a period of time before going into the outdoors. Make sure you don’t buy more boot or less boot than you need for your outdoor situations. New boots need a break-in period. Leather has to warm up to shape itself and fabrics have to have some time to bend and contour to your foot.
• ASK and ACQUIRE – know something about insulation materials, water repellency, upper materials, boot height, laces etc. Read catalogs, visit web sites, ask friends, get as much information as you can and then you will not be befuddled in the store. These are “your feet” and only YOU will be able to pick the boot that meets your comfort level and terrain needs.
• LACES – always buy an extra pair of the right length when you buy your boots and put them in your trail pack. If perchance your laces break on the trail you got them. If you need to lash, tie or bind something on the trail you can use this extra pair of laces.
• CARE – always follow and adhere to the care instructions that came with your boots. Use only high quality cleaners/conditioners. Don’t store wet or damp boots or leave them in your car trunk or truck.

SOME GENERAL BOOT NOTES:
• HOT weather – fabric/leather uppers and mesh panels
• COLD weather – all leather uppers with insulation
• REAL COLD weather – Plastic double boots or “pac” boots
• WET weather- waterproof/breathable liners – fewer seams
• ARID weather – non-waterproof fabric mesh panels, lower cut
• ROCKY terrain – above ankle, curved sole and stiff shank
• STEEP or ICY terrain – stiff soles, deep treads, high cut
• FLAT terrain – springy feel, low cut moderate stiff sole
• SNOW terrain – insulation, deep treads and high cut
• LOOSE ROCK or for climbing into tree stands – sticky rubber treads, flexible forefoot, good ankle support.