Reach down behind the headlight. There should be a gear-like device pointing to the back of the car. It should be fairly obvious. This is the vertical aiming screw. The procedure for aiming the headlights is tricky to put into words, but I'll try my best.
Park the car 25 feet from a perpendicular vertical wall. It helps if this wall has horizontal lines on it (like a garage door or brick wall).
Run a vertical piece of tape up the wall indicating the centerline of the vehicle.
Measure the height of each bulb. That is, the distance from the ground to the midpoint of each light bulb with a normal vehicle load.
Measure the distance between the bulbs.
Crisscross 2 pieces of tape on the wall at the locations of the bulbs. So, if you were to drive into the wall, the bulbs should strike the pieces of tape perfectly.
Run a horizontal piece of tape 3" beneath the pieces of tape.
Turn the lights on. The goal is for the top of the beams to end at the horizontal piece of tape. Rotate the gear until the beams are where they should be.
Conceptually, what you want to do, is make the beams drop 3 inches for every 25 feet that they travel. This way, the beams will hit the ground roughly 200 feet in front of the vehicle. Hope this helps!