Got a new big thing coming up and I'm nervous

I'm glad when exciting new things are about to happen, like starting this new project, but the anxiety before it starts almost kills me, HELP!

I wish there was a way of just reacting to things and improvising my way out. I hate the feeling of waiting for a big day, it freezes me and I can only think about the event and do nothing else for DAYS.

I hope I can survive this orz