I agree with the above.. but maybe not TOO warm. You are outside after all, in the winter, working on achieving a goal. Be warm enough to not want to quit early but I don’t think you should dress up like the MichelinMan to try to attain “Playstation3 on the couch on a Saturday morning” comfort levels. It makes it harder to handle all your equipment also, and depending on what the land is like, you could build up a sweat walking to the stand in the AM and that will surely lead to being freezing despite all the clothes on. I wear two thin wool shirts (like t shirt thickness, from first lite) and a Cabela’s wool jacket. If it’s below 25 out, I’ll also have on a regular cotton sweatshirt beneath my jacket. Typically a pair of thermals and polyester hunting pants, I don’t run cold on my legs so I might wear two layers of thermals if it’s going to be below 15 degrees all day only.
I remember my first time in a tree stand. All morning long I watched a direction I was certain the deer would come from. You are going to naturally find a clearing/path/deer trail and your brain will automatically make the assumption they will come from there, don’t do that. Keep an eye out everywhere but with as little head movement as possible. The big part about my first morning in a tree stand was that near the end of the hunt, I shouldered my rifle and to my surprise found I couldn’t even aim in that direction! Shooting as a right handed looking off to my right. So I recommend that the first thing you do when in your stand but before you’re sitting still to let the woods settle down, see how (and which hand, you will have to use both) you are going to shoulder and support your rifle (if stand has a rest for your support elbow) for any direction you might shoot in. This way you have a plan if a deer comes in from a direction other than straight ahead of you.
Don’t lod your shotgun until you are sitting in the stand.
Tie off with a harness and tree strap. Even in a ladder stand with a front rail. I utilize a lifeline in a ladder so I am tied off from the moment I step off the ground. Tree stand falls are the number one killer and injury mechanism of hunters, before cardiac arrest in second.
I’ve fallen, and with my harness on, that meant I got 11 stitches on my face instead of a funeral or broken legs and ribs.
When you sight in (and shoot at an animal with) a slug gun, hold down the forearm tight with your support hand. It’s not supposed to be loosely supported like with a rifle. The slug moves a ton slower than a rifle bullet, and the gun begins recoiling before it leaves the barrel. If you hold it loose while sighting in, it will hit several inches low when you are holding it and aiming it at a deer, with a death grip on the forend.
Look at photos of deer target locations particularly for slightly quartering shots. I highly recommend a new hunter not take a quartering shot. Too much that can go wrong. In particular look at photos that describe how you have to aim higher in a tree stand because of the angle.
Learn how to say “Meh” to make a walking deer in a good shot location stop walking. Here’s a serious video and a funny video about that:
(start at 1:30)