I'm always really nervous and hyper when I'm around the guy I like...?

Not like normal erfly hyper, like spastic everybody must think I'm insane hyper. (Please don't criticize me for this, if you can't help me, don't answer.) I don't know what to do...how can I chill? He probably thinks I'm a total freak, and also...once I chill, how do I make him realize that I'm totally normal...because I am, when I'm not around him, I swear! :) Thanks!!! I really appreciate it.