Shoulder Walk
Groove your upper body while your feet move, in this exercise where the shoulders push forward and the feet travel side to side. Start with the upper body alone: the shoulders rock, one then the other, with fists loose in front.
Then add the feet. They move opposite to the shoulders, stepping out on the heel, then a right, left, right pattern.
A picture helps: your shoulders are trying to hit a wall in front of you.