Let There be (Unobstructed) Light
We already mentioned how there's less light available at night for you to spot possible hazards. So it's critically important that you use technology -- both to see and be seen.
Let's start with your headlights. First, make sure both of them work. If they don't, replace them in pairs; otherwise you'll have one weak, dull headlight and one brand-new bright one, which is distracting to other drivers and can be mildly disorienting to you.
You'll also want to make sure the lens of the headlight housing is clean and clear. Grime and pitting from oxidation reduce the amount of light that can illuminate the road in front of you. Headlight lens buffing kits can help you restore headlight clarity and allow more light to hit the pavement, right where you need it.
Make sure both of your brake lights work, too. They give drivers behind you critical warning and reaction time when you need to make an emergency stop.
Most people know to turn their high beams off in well-lit areas or if another car is approaching. What many drivers don't know, or simply ignore, is that fog lamps should also be turned off for ordinary night driving. The water droplets in fog diffuse the light of your regular headlamps so that they have a difficult time illuminating obstacles and making your car more visible. Fog lamps are a bit more effective at cutting through fog, but their intensity can hurt the eyes of other motorists if it's a clear night.