Your best singing posture requires that you have your ankles open and flexible when you’re standing. Sitting in a chair or standing on one leg, move your foot around to feel the flexibility in your ankle. If your ankle feels tight, take your time and move it gently back and forth or in circles to stretch the muscles and release some tension.
Move around the other foot or ankle so both are equally released. After you stretch both ankles, notice how they feel. They probably feel open and flexible, as if they can support the weight of your body.
The ankle isn’t directly over the heel; it’s in front of the heel. If you pretend to sink into your ankles, you feel as if your body is heavier, putting pressure on your ankles and feet. If you visualize a spring (shock absorber) in the ankles, you can feel an opening sensation in the feet and ankles, as if the weight of the body is equally distributed.
Go back and forth a few times. Sink into your ankles and then put in the imaginary spring. You want to notice the spring not only when you’re standing, but also when you’re walking.