Side to side movements are necessary in many athletic situations. Normally this is either of very short distance (for example, moving to the side to get a ground ball) or it is a transitional movement prior to doing something else. While this is not meant to be done for long periods of time, it is important to both know how to do this well and how to use this as a transitional movement. This post is going to cover some exercises to help teach this skill.
Drill #1:
To perform drill #1 you need two cones, set five yards apart. Stand in front of one cone, facing the cone. Your feet should be hip-width apart, with your weight on the balls of your feet. Unlock your knees and push your hips back. To shuffle to the right, push off with your left foot and step with your right. Keep your weight on your heels and maintain the low center of gravity that pushing your hips back gives you. Do this for the desired distance. To shuffle to the left, push with the right foot and step with the left. To see this drill, click here:Shuffle
Drill #2:
To perform drill #2, set up three cones, each five yards apart. Stand in front of the first cone, facing the cone. Shuffle to the second cone. When you reach the second cone, pivot and sprint to the third cone. To execute this pivot, if you are shuffle to the right pivot using the left foot and step out using the right. Then take an explosive first step and sprint. If you are shuffling to the left, pivot using the right foot and step out using the left. To see this drill, click here:Drill #2
Drill #3:
To perform drill #3, set up six cones in a “T” pattern (click here to see). Stand next to the first cone, facing the top of the “T.” Sprint to the top of the “T,” once there shuffle to the right or left. When you reach the next cone, pivot and sprint to the last cone. 
All of these drills can be done for 3-5 sets, 1-2 times per week. The distances should be modified each workout to keep the drills challenging and to keep you from only learning the drills.
