Advice

First Time?
First time at a new school? First time at meeting new people? It's normal to feel nervous and a bit shy, TRUST ME. You should only be yourself and not think of what people think of you, be energetic, be more open to people because people love other persons who are fun to be with and energetic. I know you're thinking that why would you take such advice from an INTROVERT? Well, as an INTROVERT, I have observed that people hang out with the person who seems to be open with everyone at first sight. I just observed this during my first day at my temporary school.

Confronting
If you're going to confront someone, say it imeddiatly don't wait for the person to commit the same mistake and then confront them because they'll only get used to that attitude. And if you are going to confront them, do not hesitate in saying a word and make sure to give them a tip of what they should do next time. And try saying it in the kindest way possible.

Fashion
So I am just going to say this first before proceeding, I AM NOT THAT GOOD AT FASION. But I do know a thing or two in fitting clothes together so they could match. My all time favorite civilian clothes would be a white T-shirt, tight jeans and a jacket that maches with the jeans and also some sneakers to match the whole outfit. Other than that, you can also wear a long-sleeved shirt and some jeans if you want.