1) Bag hops - Start with your feet together on the foul line. Jump from the homeplate side to the OF side (keeping your feet together). Repeat 10 times. Next, start with your feet on the 2B side of 1B. Jump back and forth 10 times. After you get this down and can navigate your way around the base (without tripping), do your 10 jumps and have some one 10 feet away toss you a ball as you complete the last jump. After your last jump, get your heel to touch the 2B side of the bag. When catching it, walk out with the correct foot to get the ball. As you get more nimble around the bag, have the thrower make more difficult throws.
2) Picks. Work on all types of dirtballs...short hops, long hops, in between hops.
This should be enough to get you started.