8. Time yourself to get the winner on the first shot, and if you've got a fast burst rate, follow through for some back-up. But just wildly squeezing the shutter button doesn't necessarily lead to better pictures -- it just leads to more of them!
For more on Jack Howard's tennis photos, see his Olympus E-510 Field Test. Also check out How to Photograph Baseball and How to Shoot a Stadium from the Stands.