Start on your hands and knees. Position your hands directly beneath your shoulders and your knees directly beneath the hips. Have your fingers fully spread with the middle fingers pointing straight ahead. Make your back horizontal and flat. Gaze at the floor. This is your “neutral” positioning. When your pelvis is in neutral, your spine will be at full extension, with both the front and back sides equally long.
As you wait for the inner cue, do not sag into your shoulders . Instead, create a line of energy through each arm by pressing downward into your hands and lifting upward out of your shoulders. Go back and forth like this several times to make sure you understand the movement. As you exhale, sag into your shoulders and do the incorrect action; as you inhale, lengthen the arms, lift out of the shoulders and do the correct action.