Here’s a good way of making sure your body is centred when facing forward.
Buy a yellow stick-on-dot from a stationary store. They’re usually sold in packets and are about the size of a five or ten cent coin.
Why a yellow dot? Because it stands out against a black ‘t’ shirt or dark coloured top. If you wear a light coloured top then find a coloured dot that stands out.
Stick it on your ‘t’ shirt where your belly button is located.
Now practice your techinque, e.g. brush knee, twist step, in front of a mirror. At the end of the posture look at your reflection in the mirror and see which direction the yellow stick-on-dot is facing.
If it’s facing on an angle then you are not centred.
If you are a teacher of Tai Chi why not try this method in class. Apart from its novelty value it will give students a visual cue to see if they are centred and facing the correct direction.
Oh, by the way, when you finish practice make sure you take it off because it will look a bit weird walking down the street with a yellow dot on your belly button.