Shut off your heater/defroster controls at night to help stop snow and moisture from entering the system.
Before you set off, clean ice and snow off all windows, lights, hood and roof. Take care to clear the fresh air ducts, typically located at the back of the hood by the windshield. It will reduce fogging on the inside.
It can take 3 to 12 times longer to stop in wintry conditions. The distance between you and the car ahead is the most important factor you can control outside the vehicle. Leave more space than you normally would.
Be wary of shaded areas, bridges and overpasses. They freeze over first and thaw last; even long after the sun has come up. Watch for black ice.
In wintry conditions slow down, drive relaxed, and avoid abrupt steering, braking or acceleration.
In whiteouts or fog always use your low beams. If visibility is down to zero, slow to a crawl, put on your flashing lights, and get off the road to a safe area as soon as possible. Avoid stopping on the shoulder. Exit to a service stop, or similar "safe" area.