Start in orthodox fighting stance with your left foot and hand forward and your right foot and hand back, keeping your knees slightly bent and your hands in guard by your chin.
Perform a jab (imagine someone is in front of you and the target zone is their face). Punch with your lead left arm, keeping your elbow tight to the body and palm facing down.
Next, perform a cross. Punch with your rear right arm, keeping your elbow tight to the body, release your right heel for power and make sure your palm is facing down.
Keeping your hands in guard, bend slightly forward and to the right from your torso, elbows tight to the body (this is called a slip to the right in boxing). Envision getting out of the way of an incoming punch.
Execute the slip on your left side repeating the directions above.
Change your position to a southpaw stance (right foot and hand in front, left foot and hand behind) and repeat the drill.
Perform this boxing drill for one minute total, 30 seconds in your orthodox stance and 30 seconds in your southpaw stance. Rest for 20 seconds before moving to the next exercise.
This exercise works your speed. Modify by slowing down the tempo.