A great introduction to the single palm change.
The Pushing Palm of Baguazhang
How to Perform the Pushing Palm Posture
This posture is the Holding the Moon Posture, but your palms face outward. Some standing meditation traditions use this posture because it twists and engages the arm muscles as you stand. You can add it to your standing practice to feel the difference.
By twisting the arms, you are engaging the muscles along their entire length and encouraging interactions with supporting muscles in the torso. You can imagine that a large ball is pushing against you, and you are resisting with your palms.
Stand on the edge of the circle in the Wuji Posture. Start in the Lowering Palm Posture, then raise your hands to shoulder height with the palms facing outward.
Walk as before, and change direction with the Simple Change while maintaining the upper body posture.
Pushing Palm as a Mother Palm of Baguazhang
This posture can cause your shoulders and head to rise. Try to relax and remember the alignments of Wuji Posture. Your shoulders should remain back, not rounded forward, and the crown of your head should feel as if it is being pulled up by a string, causing your chin to tuck in and down.
In the Lowering Palm, you focused your energy down for balance and rooting. Now your energy has risen. Do not understimate the impact raising your hands will have on your posture. This seems easy enough, but it can have unintended consequences.
To illustrate this, pretend you are rubbing against the surface of a great abyss. If you lean into the surface, you will be sucked into the abyss, with no return. Don’t lean against the surface as you walk. Leaning in is easy to do because you are focusing on the center of the cirlce as you walk. The key to this posture is keep your upper body over the hips and upright.