Your feet are your foundation. Your posture begins with the way your feet, the hardest-working appendages in show business, meet the floor.
Check out your feet. Is one doing most of the work of holding up your body while the other hangs out? Is one foot propped up on the other? Are your feet far apart, cowboy-style, or primly side by side?
Our habits have determined what feels like the “natural” place for our feet. It feels comfortable to have more weight on one foot than the other, or to have our feet far apart. But this “naturalness” is something we’ve grown accustomed to, not the way our body actually functions best.
Wherever you are right now, try this. Put both of your feet on the floor, hip-width apart. (This is about the width of your fists placed side by side.) Feel as much of the floor as you can with the bottoms of your feet. Press each toe into the floor; feel the pressure of the floor against your heels and arches. Notice which elements of this may be different from how you typically sit or stand.
This exercise grounds you in your body, brings you into the here and now. When you are standing to speak, start here.