How can I make this guy more comfortable around me?

I'm pretty sure this guy is attracted but intimidated by me. Not to sound conceited at all, I'm pretty but really shy so I give off a cold/standoffish vibe due to my quietness/anxiety that i guess is intimidating, but I am really friendly when conversing. Anyways, what should I talk/flirt about with this guy so he is more comfortable with me and doesn't think i'm a stuck up chick that he has no chance with? i try to act bubbly and friendly when he talks to me but i don't know what to say a lot of the time