How to not act so shy around a guy?

I'm kind of talking to this guy we are both in our mid 20s....he's super attractive (and he knows it) I'm a pretty girl and I have a lot of confidence.... Here's the twist....ive known this kid and his family since I was 4...he was my childhood crush until I was 15! We haven't talked in a few years and randomly a little over a month ago he got a hold of me wanting to hang out.... When I seen him I was instantly intimidated because he had grown up so much and was so gorgeous... Sooooo we have more along the lines a friends with benefits relationship(we have not had sex)... And he always makes comments about how shy I am...I want to change that... In my head many handling him is easy...it's putting it into actions that's hard.....any helpful non judgmental serious advice would be helpful!!!!! Please and thank you!