As was said, Practice....
If you have an experienced friend, enlist the aid of same.
Where to practice??
Do you have anything near by that is big, paved and empty??
Go there.
How to practice?
Get some things you can see. Empty Boxes, Empty (and sort of clean) commercial ice cream buckets or, Traffic cones, if you can borrow a few. Trash cans will work too, but that can be expensive during the early efforts.
Without knowing what the rig is, I am afraid I can't be more help than that.
Matt