Don't sleep on the bases with Yadi behind the plate.

Many, many years ago when I was in 6th or 7th grade, my coach taught me (as a pitcher) to start throwing over to 1st base after a walk - do it just as the player is arriving at the base while the 1B casually hangs out near the bag. We routinely picked off players that as a matter of habit would immediately take a step off the bag after arriving. Threw out a number of kids that way over the next couple of years.

Only problem was that on occasion, it worked so well that we caught the umps sleeping too. So they'd miss seeing it.