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I generally hike in cold to cool weather. In cool weather I start the day with long underwear and cheap nylon zip-offs over them. If the day warms up and I start to sweat I pull the long underwear off and if it gets really warm I might zip off the legs on my nylon pants.
If it's cold, I'll start the day wearing a pair of fleece pants (pajama bottoms) between the long underwear and zip-offs. That keeps me cozy warm down to 0ºF.
Since the fleece pants are always between layers when I wear them while hiking they stay pretty clean and dry, so I sleep in them too.
For the upper body I wear a standard cotton T-Shirt, a long sleeve fleece shirt, and either a down jacket when it's cold, or a rain jacket if it's cool. I peel them off depending on the temps. Depending on the expected weather, sometimes I'll bring a long underwear shirt too. I usually sleep in thermal shirt and/or the fleece shirt.
If I expect to do some wet crossings I bring a second pair of nylon zip-off pants, and a full set of thermal underwear, and keep them in a lightweight dry bag.
Besides a change of socks, for a 2-3 day trip that's all I bring.
But, really, as others here have said, how much you wear to be comfortable in different temps and conditions is a personal thing. Test your clothes before deciding what to bring.
One of our longtime members here, Jim Shaw, recommends you suit up in all your rain gear and go stand in your shower for 10 minutes to see how dry you end up. Hard to argue it'd be better to find out later.
Since you're new to backpacking, I'll say the most important thing to know about clothing, I believe, is to be sure to take the time to adjust it as necessary.
That seems like a simple rule, adjust your clothing as necessary, but it's also easy to ignore. Once you're in that groove of hiking you may find you really don't want to stop, and you end up soaking wet before you do. Don't do that.
Don't succumb to that urge to keep hiking when you know you should stop and adjust your clothing.
And, while it has nothing to do with clothing, sharing trip reports with pictures of where you've been with us is also important