Get a trancent (not sure how to spell it - the tripod looking through think you see guys on the side of the road using) and find the high point that you want. Kill the grass and stake out the heights you want the ground so you can get the slope you want.
You can probably get a small tractor with a blade on the front to push the dirt. If you can just find some guys who know how to do this work it's really not that hard but you need to know what to do.
Not sure if this would be the best way to do this but this is how I would do it.