I'm meeting someone for the first time tomorrow, and I'm petrified, any ideas?

I'm scared to death to meet this guy I've been talking to online. Not because I think anything horrible will happen, but because I'm afraid he wont like me as much after he meets me. He says it wont matter, that no matter what he's going to like me, because he likes me a lot. We text each other and call each other every day. My self confidence just isn't that high. I'm so scared! Should I be? Do you have any suggestions as to how to feel better about myself? Any suggestions on how to impress a guy on a first date?