WAIT! Until it is dormant. October-November. It won't grow any more this season. Prune back the top about 1/3 and selectivly prune the rest. You'll have to dig out the other plants around it first. The ball should be as broad as the top, drip line. See if you can borrow a ball cart from a nursery but it will still be at least a 2 person job to move it.