I'm moving, switching schools and am kind of worried? How should I act on the first day?

im moving and switching schools and am i guess nervous. i never switched school districts before but once in elementary. im moving to Los angelas. will i learn how to like count cards or something haha? its kind of a rich kid school, im fraid they will be rich snobs. so on the first day of school should i sit alone and wait for someone to talk to me or should i just sit by the kids that look athletic (im pretty athletic) and start talking and say im new. or should i just sit at the end of the popular table. i dont want to sit by the weird losers on the first day of school, i switched schools in elementary and thot it would be a good idea to sit by the goofy looking people or the losers but they made fun of me for not playing halo and smacked by head and called me a noom or noob or somethig. in my old school i sat by the people who played the same sport i do, soccer. i just am really nervus, at first i was excited. but when my dad drove me by my new school i got nervous. its much bigger than my school and has 3 floors instead of 1 1/2 in my old school (half is upstairs half is downstairs kind of).