Typically I will just get a bit out of the seat. If I am trying to be a bit complicated or the bumbs look rough, I will try to unweight the front then rear wheel. I am not sure how to explain this, but I think it ends up looking kind of like a rocking motion.

As for bunny hopping on a bike with a several inch drop from the seat to the bars, my hat is off to those of you who can do it. I have no idea how that would be done.