I'm skipping freshman year of high school any tips on how to fit in?

I started school late so I'm supposed to be going to 9th this year but I'm going to 8th. I was too late to take the test this year but I am next year. But I'm already nervous. I've been wanting to skip a grade for 3 years now to be with people my age. So my first year of high school will be in 10th. Any tips on how to fit in? I'm going to a private high school and yes THERE ARE those "rich kids".