Make sure it is tuned up. Check your tires, brakes, windshield wipers, and antifreeze.
Prepare a winter storm survival kit for your car. This kit should include a first aid kit, flashlight with fresh batteries, shovel, sack of sand or cat litter, booster cables, tow rope, ice scraper and brush, candy bars or other high energy non perishable food, and paper towels.
You should keep your gas tank at least half full to avoid ice in the tank and fuel lines.