Nichov, I wish you the best of luck on your endeavour. This will be a "trip of a lifetime" adventure, no matter how it turns out.
To keep it from turning out tragically, follow the advice given above to research the trip before leaving. As a chronic cheap fart, I recommend you utilize your local library to the max in finding the recommended books to read, studying maps to establish your route, and research gear online & in periodicals like backpacking magazines.
For a "zero cost" trip scavenging will be (or become) a vital skill. Keep your eyes open as you travel, both to new materials (and uses for materials), sources for those materials, and new ideas on how to survive on the road.
Courtesy in asking others for support will also be huge, given that most of the status quo will cast a suspicious eye on anyone who doesn't present evidence of having a 8-to-5 job. Being very courteous and respectful will help overcome some of this suspicion. However, Americans can also be the most generous and magnanimous people you could ever hope to meet. Don't be surprised if/when you are supported and provided for beyond all expectation. Do be openly grateful to those who will open their hearts and resources to providing for you.
To re-emphasize a few specific items mentioned already:
- a closed cell sleeping pad or other insulating layer will be absolutely critical to keep the ground from sucking away body heat as you sleep.

Watch for a pad at thrift stores or flea markets (it is the wrong season for garage or yard sales)
- thrift stores as a cheap source of gear (Salvation Army, Goodwill, etc)
- wool or polar fleece as a winter fabric of choice (jeans are cold and binding when wet)
- the utmost importance of your boots
- using a wool or polar fleece stocking cap (or balaclava even better) to keep your head area warm
- a Swiss Army Knife (SAK) makes a sheeple-friendly multi-purpose tool to always have in your pocket
- visit the Swamp Rat Survival Forum to garner info from an expanded audience
A few other specific items:
- gaiters to keep snow out of your boots and off of your lower legs.
These can be improvised with plastic and duct tape (get a couple rolls at dollar store). For plastic to make gaiters, ask at restaurants for empty bread bags (they are semi-sturdy plastic and restaurants toss them by the bunch, so should be glad to give you a pair). To make a gaiter slit open the bottom of the bag to get a plastic tube, pull the tube over your lower pant leg before putting on your boot, then put on boot, slide bottom of plastic bag tube down over your boot top, and tape in place. If you find the gaiter rides up and exposes your boot-top to snow intrusion, pass some duct tape "strapping" under the instep of your boot to hold the gaiter down.
- cheap food
If you go to grocery stores early in the morning when they are first setting up displays, ask the worker/manager (often the mgr **is** the person setting up in the morning) in your department of choice (bakery, produce, meat, diary (think cheese as road food fat calories), etc) what they have that is going out of date or that they really want to get rid of. Often they have product that they will be reporting to their vendor for credit anyway, and will sell to you for a pittance, since that pittance becomes profit for them. Be aware that if it is a "going out of date" item that you'll want to eat it within a day or two.
Fast food joints can be a good source of small packets of salt/pepper, sugar, mayonaisse, mustard, ketchup (enough of these thinned with water approximates tomato soup), hot pepper flakes, dairy creamer (both liquid & dry) for thickening or enriching stews/sauces, plastic flatwear (fork & spoon to go with your SAK), napkins (expedient bandage material, tinder, insulation, etc), and plastic drinking straws for making Fire Straws to start a fire, as described by The Last Confederate here on Bladeforums. To make Fire Straws:
- piece of drinking straw melted shut on one end.
- cut to whatever lenght you want. (couple inches is plenty)
- stuff it with cotton ball saturated with vaseline. (Get cotton balls & vaseline at Dollar Store. Use only 100% cotton. If you can't find vaseline, you can use other petroleum-based products like Chapstick, neosporin, or other ointments.)
- melt other end shut.
- totally waterproof, then when needed just cut off end (or better, split open a side to expose more cotton) and light.
Other sources of cheap foods can be Dollar Stores, inventory disposal stores, restaurant supply stores, and surprisingly enough some drugstores and other non-grocery-specific stores (since their bread-&-butter profit items are not groceries, they can use the food items as below-cost loss leaders). Note that the selection in these stores is often limited and is a hit or miss proposition.
Understand that a restaurant can't legally give you food that a customer didn't eat due to government health regulations.
Good news for you: Wintertime packing of items on or toward the outside of your pack creates instant refrigeration for foods prone to spoilage in warmer temperatures.
- a poncho plus liner
This is a multi-purpose pair that can be (if bought/made carefully size-wise) big enough to cover both you and your pack. Using polar fleece top & bottom as sleepwear and the closed cell camping sleep pad, the poncho/liner combo will suffice for moderate temp sleeping system. For poncho, beware of the vinyl/plastic ones. They are not sturdy enough for your trip. You will want one of coated nylon. The thinsulate poncho liner sold by Brigade Quartermaster (
www.actiongear.com) is lighter and warmer than the issue model. However, you will be able to get a surplus issue model cheaper.
- merino wool socks with a polypro liner underneath
This combination of socks will go a long way toward keeping your feet warm & dry. Wet or cold feet **WILL** make your walk a misery. You can get 3 pair of merino socks for less than $10 by following links here:
http://www.swampratknifeworks.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=11;t=000992
Read this thread from the Swamp Rat Survival Forum on foot care:
http://www.swampratknifeworks.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=11;t=000027
- ranger bands
Ranger bands are cross-sections cut from a blown bicycle tire inner tube. They are typically around 1"-2" wide, but you can make them wider if you want. They approximate industrial-strength rubber-bands that you can use to attach items to your gear. Plus, rubber makes a very tenacious tinder once it gets burning. It will burn even when wet and burns for a very long time. Think about the tire yard fires you see on TV and how hard they are to put out. The long-burning nature of rubber gives you more time to dry/ignite small pieces of firewood that are less than totally dry. You may be able to get blown inner tubes for free by asking at bike repair shops, since they usually throw them away.
- keep hydrated & watch your calories
Winter saps a lot of calories just staying warm & loss through warm breath escaping. That breath also loses water vapor from your body somewhere in the 1-pint/day range. Your water consumption will have to replace that, plus other water lost through sweat (an appropriate walking pace will keep you warm, but *NOT* sweating, which is your enemy in cold weather), digestion of food (proteins especially), and urination. Caffiene also is a diuritic (sp?) that loses you water from body cells, so go light on it if you can. IIRC caffiene is also a vaso-dilator which will cause you to lose even more body heat.
Understand that each food group has good & bad attributes:
- fats have a high calories-per-weight ratio, but storage can be an issue
- proteins provide long-term energy but are harder to digest
- carbohydrates digest easier than other groups, thus providing quick energy/warmth
(some specific foods below)
- peanut butter gives you protein & fat, plus a plastic jar of it packs easily.
- honey provides quick sugar energy. It also gives mild antiseptic protection to a burn (chill the burned skin first, otherwise the viscous honey will hold the heat next to the skin = not good)
- warm tea, especially green tea (lower in caffiene concentration than coffee) will be a valuable friend gives you core warmth and liquid hydration, plus antioxidants. A dry used tea-bag makes a good bandage to stop bleeding. The mesh/paper of the bag provides a rough texture for the blood to clot against and reports indicate that there is something in the tea that helps the wound. Sorry, I don't remember what it was.
- warm up before bedtime
Eating warm food, then walking another mile or two to get your body generating internal heat will give you a build-up of heat to get you through the initial warm up of your sleeping system. It's kind of a thermal head-start for your sleeping time when heat production is lower (almost no muscular action to burn blood sugars & circulate blood/heat around your body). IME walking also helps avoid the "lump in the gut" syndrome if I eat heavy/dense food (canned beef stew, for instance) before bedding down for the night.
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Again, wishing you the best of luck with your walk. Stay safe, be warm, have fun, and appreciate the adventure of it.