Do easy moves you know, but add a little twist. Change your body angle and face a different part of the crowd. Or change just the angle of your hips. Or just your chest. The tiny change gives things a really different look sometimes. Try different arm positions. Use tiny little head slides or chest pops to accent some of your counts. Don't be afraid to get down on the floor. And don't forget to use your space and work your crowd -- if you practice in front of your bedroom mirror, chances are you'll dance in the same amount of space for performance, even if you have a big open floor. Throw in some turns or traveling shimmies or whatever and use the room; it totally uses up music and time too if you're out of ideas. It always helps me to write everything down and be able to look at it, whether it's total brainstorming, grouping moves together into families, outlining a plan for practice, or mapping out an entire choreo.