Are you trying to double them?
IF not, then you need to drag the rear brake a little before the jump to get straight, stand on the pegs, and give it a little gas on take off aiming for the downside of the hill or just in the flat. That way you can prep for the next jump. Since the hills are 12 feet or so apart, that is perfect for a double, that way you can carry some speed and finese.
IF you are going to single them, that is definately going to be slower and a little less clean. Lean back with arms pretty straight for that downhill stuff so you don't endover or lawndart.
Sly