Next time, use the search button. This has been posted zillions of times.
Anywho, one of my favorite drills is to do 1vX (X being how many players you have left -1)The team of one gets a gun. The rest do not. The one guy must go to back center and stay in back center. While the other team who does not have markers need to press up the field and tag his bunker without getting eliminated. Very fun if you are the one
2v1 are also very helpful. It teaches the team of two to close out games and the team of one to turn the game around.
Snap drills are extremly important. I do these every practice.
Practice run throughs by setting cones in bunkers and running down and bunkering the cones.