Please help me I will help u !!?

I have this best friend and I like him since he broke up with his girlfriend and he liked her again but he doesn't anymore..I like him for his personality not looks..he would go out. with me but he doesn't want to because he thinks I'm not very pretty..should I tell him the reasons why I really like him..or should I give him some time..if tell him the reasons will he feel the same way?..we flirt and we have been best friends for 6 years..I've seen him stare at me a couple times and he has let me have a drink of his dr pepper and we have a lot in common!