I make sure that any coat I buy has enough room to wear layers of clothing under it. Layers are what keeps you warm, one should have a high neck. A hat is surprisingly warm, especially when it's windy, and ear muffs are not just decorations. You will feel much warmer if your ears are covered. Ditto a scarf which sort of fills up the drafty places in your neck area.
If your coat has a drawstring at the waist like an anorak, cinch it in to keep drafts from getting to your upper torso. Your coat should have a collar that you can pull up and if need be button in that position.
Mittens are generally warmer than gloves, but I must say I have a fleece lined pair of gloves which are just as warm as mittens.
When it gets bitter cold, then it's time to break out the heavy duty things like silk underwear-leggings and undershirts, face masks, bib type snow pants, sub-zero rated winter coat with an attached hood that can snorkel, preferably with a fake fur ruff on it, probably down. And the coldest rated boots that you can get with good traction and an extra size larger for heavy socks. Make sure your boots aren't "sock eaters". Then if the snow is really deep, gaiters.
And don't forget YakTrax.
And you will need a coat for your dog and if you get very cold weather, boots for the dog too.
There now, I think you'll be ready. Is it more information than you wanted to know?
Oh, you will look at least one hundred pounds bigger than you are.
