What is best way to cover everything with only one-umpire?

[Jeffhead]

Patrick has made some real good comments in his post above. The only thing that I would add that my association drills into us is "angle over distance". Work to get a good angle first and then close the distance to the play if you can. Best would be to get both but in large diamond single man that happens rarely. Especially if it looks like there may be multiple continuous plays.
Jeff