A leg band will be necessary for this exercise. A makeshift band could be made from a pair of old socks tied together to form a band. Place around thighs, knees or calves depending on looseness of band.
With band around both legs, walk in forward motion, one foot at a time. Move right foot forward, then bring the left foot to meet the right foot. Once both feet are together, move left foot forward and then bring the right foot to meet the left foot.