Always a problem Mr Rage, particualalrly with big boards. Light ones are harder too because the wind wants to take them away.
With 4 x 4's being that bit higher you don't have as much control because you are stretching up the whole time.
If you have a Land Rover Discovery 3, drop the suspension as low as possible.
If not, Park next to a kerb so you can be a bit higher on one side.
Have a small fold up step ladder.
Definitely keep the nose into the wind.
Put your straps on the roof racks first so that you can grab them quickly and put them over the board.
If you have a drop down tailgate, stand on that and feed your board onto the racks.Keep the board as flat as possible.
If I think of more i will post them.
Oh yeah, keep smiling!
ET.