Just be neat and generous. Girls are usually skirts, and boys are usually suits. If it is organized by the school, because all students can wear school uniforms. It is also possible that boys have white shirts, black or dark pants and black or dark shoes; Girls can wear a white shirt, a red plaid skirt or a short black skirt, plus black shoes. You'd better wear the same clothes as boys. You can tie a red bow tie on your shirt. Girls can also wear long white or red skirts.