Big can of worms you're opening up here! There are so many types and ways to jump that it's hard to say one right way. There are seat jumps out of turns that you are sitting when you leave the jump and standing when you land. It's best to land on the front wheel down first usually but then that could change on how the landing is. I think it would be tough to give you a definate answer without knowing what type of jump you're talking about.
See if you can be more specific on what you need then someone here would probably be able to point you in the right direction. Good luck
Elk