Make sure your wipers are free when you start your car - check them 30 minutes after a trip on a cold day.

Wash your windshield when you get home - everything is warm and you will get fewer scratches if you have to scrape it tomorrow. Use snow if available, wipe the entire surface - I keep a squeegee in the car.

Warm your car fully on really cold days even if you have to run it at a high idle when you get home.

On really cold days, do not run any extra accessories like power seats, power windows, or mirrors if you do not have to. They may be frozen.

Wipe down door seals with high quality silicone a couple of times each winter - use a silicone spray that is safe for rubber and plastic - some cheaper products use propellant that damages those items.

If it is cold and dry, crack a window to allow the dry air to remove moisture from your car - vent visors are a good investment. If snow is expected, crack a window down wind.