Aim auto headlights in a way that allows the driver to see as far as possible, without blinding oncoming traffic. Re-aim the headlights every time you change a bulb, or when the car is carrying a significant amount of weight.
A common way to check and adjust headlights is by parking the car at approximately 25 feet from a wall. Adjust the headlights so that the low beams’ hot spots rest 2 inches below and to the right of the low-beams' centerlines. At approximately 12 feet from the wall, the bean should not be higher than the hood of the car.