If you are going to participate in a grandprix or yagp you will need to present a variation or pas deux of a classical ballet. In each of the two cases you will have to play a character for which you will need a specific costume or tutu.
I will list below the main characters to interpret, suggesting you some links of costumes to wear.
1) In Don Quixote ballet you will find:
Cupid VariationKitry first actFlower girls,MercedesKitry Grand pas de deux third act.