The first day of school is the most important day of all years in school because you show yourself off in front all the teachers. You should talk a lot like Hermionie Granger and show that you know a lot(show it either if you're not that smart). Do those things but anyways don't act fake. Don't act like Draco Malfoy. But you should act how the teacher wants(depends on what their mood is or how they act). I realy don't understand teachers sometimes. The couple first years teachers are good but when it comes to last years they get so bad.