Grace comes down to three words:
“Things moving freely”
Those three words are exhibited in the cosmos and are the way of graceful animal movement.
In the case of animal movement what is preventing graceful movement? Structural issues aside let us focus our gaze on the nervous system.
Ask yourself this question with experience and not words:
How is your nervous system holding you?
When lying down on a firm surface yield to it and see how you are lying are you holding yourself even when the unyielding surface can support you?