When I walk around town in a more "tai chi" way, for me that means staying grounded on the weight-bearing foot and using a slight pelvic split to move the other leg forward.

When I do this, my head naturally moves slightly back and I stand more upright. Most noticeably, my shoulders loosen up and my arms swing in a wider arc. This all happens naturally without any additional effort or guiding on my part.

An interesting connection between the feet/hips and the upper body. It feels pleasant to walk this way as well.