Can't offer you any operational tips, but can remind you that you always need to call Diggers Hotline before you do any digging so all of the utilities are identified. Otherwise, like Hoeman00 said, it could go BOOM! Also, if you're planning on hiring out with it, you absolutely need to get contractor's liability insurance. Don't even consider using that thing off your property without insurance.
Good luck and have fun! /w3tcompact/icons/wink.gif