A big part of footwork is quickness, and the best tool I know of to improve quickness is a speed ladder. I would highly recommend getting one—the longer the better. The various drills and exercises are pretty easy to find and learn, and they're pretty fun to do.
You can just Google "speed ladder drills" and you'll get plenty of sites that do a far better job of explaining the drills than I can. Then get your team on it: warm up, stretch, then run through the exercises at the beginning of practice or workouts. I'm no fitness expert, but I've heard it's better to work on speed and quickness at the beginning of a work out as opposed to the end when you're tired and less likely to use proper form. Whether that's entirely true or not, I'll leave for you to decide.
Anyway, you can get by with one ladder for your team, though I prefer not to run more than 10 people on a ladder just to keep the down time to a minimum, so two usually works better when you've got your whole team together. I guarantee you'll see results. (Note: Results not guaranteed in any real or meaningful way).
As for individual footwork "moves," one that can help make cuts sharper is planting off your inside foot instead of your outside foot (or a cross-over step). For example, say you're setting up a cut to the left by heading to your right. When you're ready to change direction, the typical move is to jab your right foot out to plant and push off to the left. Try this instead: place your last step with your left foot under your center of gravity, or more to the right of where it would land if you were running straight ahead. Rotate your hips hard to the left, and swing your right leg around to make your next step roughly 90 degrees from your original path. It will also help to get low and dip your left shoulder as you make the move. You should see that this will allow you to change direction quicker than with a jab step.