Here is what a California girls learns from short periods of time in winter. First, you basically look the same every day. The big coat and scarf are necessities to survival, and since most people don't own a closet full of coats, you just sort of have them on repeat…every day. Same boots, maybe switch the jeans from grey to black, and the shirt is rather irrelevant.
Second, winter is heavy, for the amount of clothing weighing down my shoulders I figure it's a few of the push-ups I need to do every day. I never do push-ups.
Third, feet matter! I never thought about my socks before, if they cover my toes it's really all I'm looking for in a pair of socks, and sometimes they don't even do that since I buy them once a decade they tend to wear out a bit before being replaced. A friend recommended wool socks and without them I would have been a significantly sadder person for it. Also waterproof shoes are super helpful, I will educate you and tell you that they keep the rain out of your shoes which will add significantly to your quality of life because when your feet make a swooshing noise every time you take a step, you probably aren't a super happy person.
Final pointers: get an umbrella that doesn't invert itself the moment you open it, they can be avoided by never purchasing anything ever from a store with any sort of eiffel tower paraphernalia in it, and don't buy new natural deodorant right before a trip because it may not work and it gets warm under all seven layers.
Cheers! Let me know if you need more advice.