Aiming Driving Lights

Hey All

Quite simply, is there any hard and fast rule/way to set up your driving lights PRE- TRIP. I mean you can set up your vehicles factory lights by following the diagrams in the factory manual, but where is there a chart or dimensions for setting up the many different variables involved in driving lights. There is nothing worse than when you go to use the buggers and they are nothing more than possum blinders and you have to get out with a shifter in the dark and reposition them.

Any ideas would be appreciated
Andrew T