I recommend the 'cross-over' method, of using your right hand on the 'z' and 'x' and your left hand on the arrow keys. Only helps so much, but still better than trying to control movement with your right hand. I still don't get why everyone insists on mapping games to this style when every console ever uses 'right hand = movement; left hand = action buttons' mapping. They should map it to WASD and ',' '.' or something.
Edit: As pointed out in the replies below, that should be 'left hand = movement; right hand = action buttons'