Instructions
Move the left analog stick on your PlayStation 3 controller to guide your active player. The highlighted player will move in whatever direction you move the analog stick.
Hold "R2" to make your player sprint. This increases the speed at which the player runs, but it only works for a short duration.
Release the "R2" button to allow your player to regain his stamina. This only takes a few seconds.
Push the right analog stick up to switch to another player. This becomes the active player, and you can press "R2" to make this player run faster.