The potential smile — could you smile, if you wanted to?
Have you ever noticed that most images of the Buddha show him with a Mona Lisa-like subtle smile?
The potential smile is a sign that your awareness – your command centre – is clear of any influence from your thinking, emotions, body and the world.
It's a close cousin of the wonderbreath, which opens up area, getting the parachute full of air. Together they act as a gate between your torso and head. There will be all sorts of healthy tension in your torso, but we want to minimise all tension above the throat bandha.
Check that your body/torso is engaged, and check that you have access to your potential smile.