One of the most important things in baseball is having healthy, strong, and stable shoulders. One of the best ways to accomplish this is by forcing a baseball player to move their entire body through their arms. One of the many variations that accomplish this task is the basic shoulder walk seen in the video below.
You want to keep the arms locked, reach out your hand, and pull yourself forward using your shoulders. This is not a bear crawl or other form of animal walk so your hands will not ever come up off the ground. Instead it is more of a scooting and pulling motion to move the body.
Check out the video and let me know what you think.