What should I say when I call?

Ok, so last night I was training as my first night as a waiter. This girl came in with her parents, and she was stunningly pretty. I noticed she was checking me out and smiling at me when I looked, and I smiled back. When her and her parents left, I went to clean up the table and found a napkin with her number (I'm uming) on it. I'm gonna call tomorrow and I'm hoping that she left it for me like I supposed, but I have no idea what I should say. Any ideas?