Like any normal child, I learned how to stand up as a toddler, or at least I thought I had. At some point I had learned how to stand in a very unhealthy manner, making my whole lower body hurt when standing long periods. When going minimally shod, I decided I needed to re-learn how to stand and walk.
Now I don't just stand there, but feel and acknowledge the parts of my feet holding me up. I consciously rest my weight evenly on all parts of my foot. I have to lean forward a bit or bend my knees to make it work. My foot spreads a little more to carry the weight over a greater surface. When doing it right, I can feel the individual bones of the foot each resting on the ground.
I am using my new method of standing up like a good posture. Whenever I catch myself slouching my spine or my feet I straighten up and stand right. My feet still hurt after standing a long time, but it is muscle fatigue, not stress injury, and passes in a day.