Emphasizing brilliance:
* Sparkled like a thousand tiny stars
* Sparkled like scattered fireflies
* Sparkled like a field of dewdrops catching the morning sun
* Sparkled like a scattering of precious jewels
* Sparkled like a shimmering pool of liquid gold
Emphasizing movement:
* Sparkled like dancing flames
* Sparkled like a cascade of falling water
* Sparkled like a flurry of snowflakes
* Sparkled like a wave of light
Emphasizing vibrancy:
* Sparkled like a rainbow after a summer shower
* Sparkled like a bed of colorful blossoms
* Sparkled like a burst of fireworks
The best simile for you will depend on the specific context and the effect you want to create.