http://www.infobarrel.com/How-To_Perform_Plyometric_Box_Jumps published August 5, 2008

How-To Perform Plyometric Box Jumps

by tRex Box Jumps are a great plyometric exercise which are great for developing functional leg strength which can greatly benefit athletes in many sports.
  1. To perform a box jump, first stand facing the box with your feet just wider than hip-width apart.
  2. Next, lower your body into a partial squat position and as soon as you hit the lowest position, immediately jump up onto the box.  You want to make this one swift movement with no pausing at the bottom.
  3. Your feet should land gently upon the box, the gently step back down.
Box Jump Demonstration Video