When I lived in Michigan, I had 2 sets of Dunlop Graspic snow/mud radials on some generic OEM wheels that I used from approx. November to March. In addition:
- Changed out OEM floor mats and replaced them with heavy duty types that were for winter
- Kept 2 gallons of windshield solvent in my trunk <--- always using this because of the road salt
- Kept jumper cables, blanket, gloves, flashlight, road salt, extra window scraper, lock de-icer, and small snow shovel in car (some in trunk, some in glove box)
- Checked coolant/antifreeze concentration with one of those bulb meters, added if necessary (flushed and filled system every three years and replaced thermostat)
- Checked belts, hoses, spark plugs, filters, etc.