Cotton socks, which first absorb moisture and then stick to the skin, are right out for hiking or any serious athletic activity. Blisters on the bottom of the feet is probably due primarily to the socks not wicking away moisture and sticking to the soles, and once that starts the blisters tend to be self-reinforcing. Not only would I suggest that you get good wool socks like SmartWool (and yes, they come in different weights; you should select sock thickness that correlates to the weather you are hiking in and the fit of the boot), but I would also recommend using polypropylene or silk sock liners. These will help wick away sweat or moisture that may cause the sock to stick to your feet and start abrading to a blister. While wool socks and sock liners may not completely eliminate blisters they go a long way; I can’t remember the last time I had a blister when wearing appropriate socks.
I usually carry a few Moleskin patches but I’ve rarely found a need for it when wearing good boots and socks, so mostly I end up giving it away to other people, or using it to cover abrading seams in clothing or kayaks.
I also generally carry at least one spare pair of socks and sock liners, because they don’t take up much weight, are great to change into if your existing socks are totally saturated, and can be used for other things like mittens in an emergency. I’ve hiked miles in wet socks with liners without a problem, but when your feet are frozen cold it is such a relief to change into warm, dry socks; in fact, this is usually the first thing I do after setting up camp and rolling out the sleeping bag.
Good boots, or at least robust, good fitting shoes with good traction, are also a necessity. If you don’t know what to look for I would recommend going to a good outdoor store and having them help fit you. Boots are definitely not something to skimp on, especially when carrying a backpack. You don’t need to splurge on custom made Danners, but work boots are probably not adequate. I’ve seen people hiking in tennis shoes–some people prefer it–but I find that they don’t provide enough arch support for carrying a load, and traction on normal tennis shoes on trail is inadequate. The boots/shoes should be firm but not tight or constricting, and there shouldn’t be any significant movement of the foot within the boot either ascending or descending, or if there is movement it should be in a way that the foot is free to move without rubbing. For instance, I usually adjust the tension in my laces to hold the ball of the foot stable but intentionally allow a bit of heel slippage on long, steady downhill trails because I find that my foot tends to slide toward the front and trying to put enough tension to keep the foot from moving at all results in heel blistering and squeezing of the front. You have to figure out what works for you by trial and error, though.
I actually have three sets of hiking boots (all Vasque brand, which I find fit me very well and hold up longer than other boots I’ve had), depending on whether I’m doing casual hiking, warm weather backpacking, or cold weather heavy backpacking. When just doing a casual hike with a light daypack or beltpack I often just wear trail running shoes (cross trainers with aggressive tread). If you hike a lot (or would like to hike a lot), good boots are a wise investment in comfort and foot health; getting corns or infections due to blisters is no good for anyone.
I hope this helps. Good luck, and enjoy hiking.
They’re not bad, actually. Wool wicks away moisture (and therefore evaporates and cools) much better than cotton. I would wear thin wool/silk blend or merino wool socks. I personally prefer to wear full leather uppers and steel shanks, but most manufacturers make lighter boots with fabric or even ‘see-thru-em’ uppers that allow ready ventilation. Your feet don’t really produce that much heat, anyway, so when hiking I rarely notice that my feet are hot though taking off the boots at the end of a hike and planting my feet in a cool lake or stream is one of the refreshing joys of hiking.