The most important choice you have is what to wear on your feet. You already know what type of shoes you will be wearing in the show. If you're wearing heels, practice in heels. If you're wearing converse, practice in converse (or a similarly flexible shoe). No matter what, DO NOT wear flip flops or other sandals, and DO NOT go barefoot in the theater. (Andrea will try really hard to set a good example of the no bare feet policy.)
Keep in mind that you will be dancing every day. It is a great idea to wear flexible clothing that will move well with you. Many students find athletic shorts, lounge pants, or leggings to be great options. You can certainly wear jeans; just remember the focus should be on how well you can move, not on how you look. When it comes to shirts, the best options are items that fit well and stay in place with no fuss. Constant tugging and pulling at clothing during choreography rehearsals is a distraction to both you and the choreographer.
Be respectful of those around you. Remember we have a variety of ages (8 to 18) involved in this production. Please dress in a way that is appropriate for everyone around you. Although there is no specific dress code for EYT, please consider the length and cut of your clothing and how it may fit when you are stretching and dancing.
Don't forget important details like deodorant. The stage area is small, especially when all 72 of you will be crammed together for activities. Shower daily. Use deodorant. Bring deodorant to reapply later if you need to. Go easy on the colognes, perfumes, and body sprays. Let's try to make the theater smell like a wonderland. :)