I layer synthetic, fast-drying wicking performance as first layer of underwear. Then if need long underwear will use a wool or wool blend. Camo shirt on top of that. Fleece vest then the outer coat.
Depending on weather, will skip the long underwear, the vest. Or, will go with a parka rather than outer coat. My outer layer is water-resistant if will be around wet vegetation or expect rain or snow.
I always wear two layers of socks. The first layer is thin and synthetic wicking material. out sock is heavier wool blend and thickness varies on weather. I make sure each sock goes on with no wrinkles, especially on the underside and toes of the foot since any bump in the sock will promote hotspots and most likely create blisters.
Wear mittens that have a folding back flap if very cold, otherwise gloves. Baklava if windy and cold to protect face.
Use a fleece cap if cold, ball cap if merely sunny.
Though almost all of my hunting is in the east, I still layer. I was using all synthetics but have decided to try merino wool because the synthetics always got a little gamey after extended use. I am hoping that the wool helps with that. I also use leg and neck gaiters to layer as they often help just enough on chilly mornings and don't take up much room once it warms up. I generally only use a light weight baselayer but also have a midweight if its really cold. I prefer this to two pairs of pants because it is lighter and more flexible. I prefer a waterproof shell for a coat and just got a packable down jacket for warmth. I pack rain bibs if its calling for inclement weather. I prefer not to wear waterproof pants because of snagging them too easily.
I skip the synthetics. Minus 33 wool for a base layer if temperature warrants it. When the temps are really low, I make sure my top layer is windproof and that usually means rain gear. I have an old set of Cabela's Rainsuede for my windproof top layer, unless I'm expecting rain or snow. That Rainsuede is quiet and windproof, but I can't get it to keep from absorbing water any more no matter how much DWR I put on it. When I'm expecting precipitation, I go with First Lite on top. Minus 33 is great wool at half the price of "name brand" hunting wool.
I usually start with the merino zip t or core zip t, if needed will later add top with traverse zip t, 90% jacket and jetstream vest. Still need to pick up the jetstream jacket. For bottom usually just the mountain pants but keep the merino or traverse bottom if needed. Also the merino boxer is much better than I expected. Still have a couple of more pieces to get yet but almost where I want to be with my system.
I walk around like a wood stove on full "stoke"!! I use mostly the poly pros that I have gotten courtesy of Uncle Sugar and have to be down to just silk weights on top when moving until the temp gets well below 20. When I stop I go to mid weights and a wind shell along with gloves (temp dependent for which level) and fleece hat. On my feet I use poly pro liners and merino wool of weight specific to just how cold it is. There may be slightly more efficient outfits but for the cost (0), I can't do better for me BTW, in the case of extreme cold I have prima loft goodies in reserve.
Light weight wicking/cooling base layers on warm days.
Merino wool or Capeline if colder. They don't get stinky,and work
Micro-tex pants&shirt. Berber fleece vest.
Cap and fleece balclava.Fleece&neoprene light gloves. Wool gloves w/mittens.
Rain suede parka/pants.Kings Mtn parka w/removable jacket if cold/wet/snow.
Berber windshear hooded jacket and pants if snowey/windy/dryer.
Down parka and sweaters as back up......
Merino socks,and lite liners. Gore-tex Gaiters. .
I've gotten into the wool game in the past few years and have been trying to simplify my layering kit recently. I go wool boxer briefs and socks and First Lite Kanab pants on the bottom. I'll run really light long underwear if it's cold out. On top I go FL Llano quarter zip, a light primaloft vest, a light puffy and a rain coat. Ball cap, fleece hat, neck gaiter and a light pair of gloves round out the accessories. I'll add mitts if it's really chilly.