What I'd tell my 18 yr old self:
-You will eventually get over this awkward/shyness crap, and a lot sooner than you think.
-Get a canoe. Any canoe. DO IT NOW!
-Don't be afraid to go alone... if it's not important enough to people to get outdoors regardless of the weather, they're probably not made of the right stuff, and you'd probably end up babysitting them anyway... So when they back out, leave 'em be, go alone, and don't invite them again.
-Save up money for your better future canoe(s)... eventually, you'll want a good solo tripper for the kinds of places you usually go. Don't hurry though... with age comes income and savings. You can't have everything right away.
-Buy good stuff once... quality lasts... Get a Norlund hatchet and ax, and a good 24" bucksaw. You won't take them every time, but when you do, they're good tools. If you can afford a 32" bowsaw, it's worth taking on easy trips.
-Don't bother with a fancy cookset. You don't like to cook anyway, so just learn to dehydrate stuff and boil it in one pot. Don't waste time with the little sub-quart-sized pots... you'll need a bigger one to boil dishwater and to keep a pot going over the fire after dinner for soup, cocoa, and tea anyway. Best of the lot is a German Mess Kit. and make a pot chain for it. Find one lexan spoon you like, and rig up a Kool-Aid jar for a bowl/cup, with a cozy for them. You CAN make bacon in a frying pan, but it's good on a stick too, like marshmallows, and the stick doesn't weigh anything.
-Have a backup stove, but you were taught to cook over a fire for a reason. That backup stove should be an MSR Pocket Rocket. While we're on "Fire", learn to make a flame in any weather conditions, and keep the materials for it on your person at all times. Nature is not going to care if you die of hypothermia or not... so there's nothing wrong with "cheating", as long as you are competent the "hard" way. Flint and steel, firesteel, and bowdrill are critical.
-Forget that whole tent thing. Go straight to a hammock, underquilt, and good tarp.
-Clothes. Don't buy anything special, and don't carry so much. Use a good USGI poncho for raingear... forget trying to keep your legs and feet dry, just like the Army. You don't need clean or dry pants. Just rinse out what you have while wearing your longjohns. Same with an outer shirt. You don't need an extra one. In t-shirts, one synthetic for daily wear and one cotton one to sleep in are all that's needed. Take two extra pairs of high-quality/high loft wool socks. You may eventually decide you only need one extra pair. Oh, and bring a stocking cap in addition to the brimmed one. A spare pair of underwear is not essential, but may be useful. A wool base layer can't be beaten. You only need one extra "layer" over that. Below 40*, stay home. Above that, the USGI wool field shirt, or a fleece, is plenty so long as you're moving. Your poncho can double as a wind breaker. If still cold, saw and split more wood (see below).
-Backpack. Keep it simple. One single compartment, comfortable straps, maybe a couple water bottle pockets and a zippered exterior "junk drawer".
-Water. Polar Pure/sublimated iodine crystals. You'll get over the iodine taste. Man up, or be forever tied to a filter.
-Camp setup, after you unload your gear, tie off your canoe (both ends!) and secure the PFD and paddle(s):
First job is to set up the tarp and get your hammock under it and gear up off the ground. That way you have somewhere to go if it starts to rain. This should take you about 10-15 minutes at most.
Second job is to find a 5"'-7" standing dead maple, saw it into 6'-8' sections, and carry it back to camp. Spend some time immediately in processing about 3'-4' of it into quartered or eighted splits about 9" long, and get it under cover. This should take about an hour. Spend a few more hours over the next day making more. (You can make your first meal at this point.) Do not chop at night.
Third job is to arrange your firepit/kitchen comfortably/conveniently. Make a spot to put your chair/seat, with the food pack/wannagon up off the ground (even on a couple pieces of round softwood, so rainwater can run under it) nearby. Find a 1/2" stick with several forks cut short, maybe 2" per branch. Drive this near your foodbag/wannagon as a dish rack. Rearrange the fire pit, with a log or rock reflector about 2' tall for the smoke to climb, so it isn't blowing in your face the whole time. Lay down logs, splits, or rocks to support your grill/pipes if you have them, or make a tripod for the cookpot chain. Level a spot next to the fire to set your pans on, up out of the dust, so nothing gets kicked into them. If you carry a wannagon, the lid works well, especially if it has a raised lip around it. On the other side of the fire, make your wood rack... half-splits 12"-16" long for campfire wood at the far end, 9" quarters (or even finer) for making cooking coals closer at hand, with kindling/tinder on top of that pile. Two rounds of anything about 3'-4' long will do to keep it all up off the ground (and out of any rainwater), and 3 sets of 2 stakes (left, right, center) will keep them organized. Look for tinder whenever you're away, replenish often, and bring back whatever you find. If you end up with too much, the next guy will surely appreciate it. This latter bit of "polishing" the camp will only take an hour or two, but is OH so nice once it's done. If you can, always lay in your fire before you leave camp... you may need it in a hurry when you get back
Miscellaneous:
-Cinnamon Raisin bagels seem to stay moister longer than plain bagels, probably due to the raisins.
-Tea is better than coffee on a trip because you don't need sugar or milk with it, nor special eqpt to make it.
-Cocoa is both a physically and emotionally/mentally strengthening beverage... nothing better when you're cold and miserable.
-Putting similar meals together in one bag seems to be pretty efficient... all the breakfast stuff in one bag, all the lunch stuff in a second, all the dinners in a third, and all the drink mixes in a fourth.
-Re the down vs synthetic argument... turns out that down won in the end. Just always always always keep it dry.
-Get a dog to keep bears and coons out of your food.
-Get a headlamp. A flashlight has few advantages over it, and you only need one. It's good if all your batteries (camera, lights, GPS) are the same kind.
-A fisheye compass is about all you need for your canoeing. You're going to learn how to navigate almost entirely by terrain association within a couple more years anyway, just like that SGT at fort riley told you. And you won't use your GPS for much, so get an old used one for cheap.
-You can get by on a really small first aid kit, so don't waste money on a store-bought one... moleskin, bandaids, dental repair kit, antibiotic cream in single use packs, and a small container of OTC pain relievers and stomach med is all you need.
-Read Kephart's Camping and Woodcraft sooner. He's pretty much got it down.
-In the South, replace your ax with a machete. You don't need both, and the machete gets used WAY more.
-If your trip is so easy you decide you can afford to bring a tarp and wannagon, bring a big tarp. not a small one, and set it up as an A-frame (one cross rope and 4 tie-outs). Might as well be comfortable.
-Bring a fishing outfit anyway... sure as you think you won't fish, you'll want to, and it's light.
-Go lighter vs heavier... I have never yet truly regretted not bringing something.
-Rice is stupid-simple, despite how hard people make it out to be. So always carry some for an emergency. Ground/dried navy beans too.
-Think stuff through... determination is all well and good, but remember the bulldog... too much can get you killed, and that's way easier to do when you're soloing. On the other hand, "go quietly, alone. No harm will befall you."