Clothes make the man! People say that, right? I’m pretty sure I’ve heard someone say that. Anyway, for backpacking and hiking in general, it’s absolutely true.
Lightweight, packable, comfortable: these are key words to keep in mind. You’re going to be carrying enough weight in your pack in the form of water, food, tent, and everything else. For a 7-day trip I generally pack: 1 rain shell, 1 midlayer insulator, 2 base layers shirts, 1 pants, 1 shorts, 2 pairs of socks, and (unfortunately) 2 pairs of underwear, 1 pair of gloves, 1 insulating hat. LEAVE YOUR BRA AT HOME. Fuck it, throw your bra away. Fuck bras.
A rain shell is a lightweight packable jacket that is waterproof and, preferably, windproof. An example of a midlayer insulator would be a waffle fleece or suchlike; I pack my trusty ArcTeryx Atom LT jacket. You can get one HERE: https://arcteryx.com/ca/en/shop/womens/atom-lt-hoody And honestly, I do recommend getting one. It’s absolutely worth the price. I love mine!
This is more than a love-fest for the Arc’Teryx Atom LT jacket though. My laundry list above of the clothing I bring on a 7-day backpacking trip may look minimal, but it’s really all you should need. The trail doesn’t care if you stink. Honestly, neither my partner nor I smell our stink until we’re back in the car (where you should absolutely have a change of fresh clothes and a thing of deodorant available upon your return.) The trail doesn’t care if you’re dirty. The trail doesn’t care if you walked around wearing the same outfit just two days ago. And you damn well better not care because if you bring extra stuff then that’s just more weight to carry and more stuff to take up valuable room in your pack that could otherwise hold another pouch of freeze-dry dinner or another bag of water.
You’ll get mixed recommendations on wool vs cotton vs synthetics vs etc. Whatever. They’re all right, and honestly they’re all trying to sell you something. Lightweight, packable, comfortable. Lightweight, packable, comfortable. Lightweight, packable, comfortable. These are the keys. I don’t get any more philosophical than that.
Oh, and one more thing: if you’re going into the mountains (which honestly is where most backpacking trips go isn’t it?) then do not pay attention to the weather forecast. Or, if you do, take it as a general guess; which honestly is always how I treat weather forecasts anyway. The mountain does whatever the fuck it wants. The trail conjures up whatever weather it fucking wants. If you layer as advised, you should be prepared for temperature fluctuations. Remember: you WILL warm up as you hike. TRAPPED SWEAT IS YOUR WORST ENEMY. If you are sweating, shed a layer. Your sweat is designed to cool you as it evaporates. If it can’t evaporate, you will be miserable.