Movement:
* As graceful as a swan gliding across the water.
* As graceful as a dancer twirling in the spotlight.
* As graceful as a willow swaying in the breeze.
* As graceful as a cat leaping through the air.
Other:
* As graceful as a melody flowing from a violin.
* As graceful as the lines of a well-written poem.
* As graceful as the sunrise painting the sky.
* As graceful as a snowflake falling from the clouds.
The best simile will depend on the context of your writing. Choose the one that best captures the specific type of grace you want to describe.