How to get a guy to ask you out

I've been knowing this guy for almost 2 years. I even dated him for 3 months last year (I decided to end the relationship because I could feel myself getting attached and I was scared, but it didn't end in a big fight). We're really close friends and we talk to each other everyday, but I'm afraid of rejection. I know he likes me because he's always touching me, he got a little jealous when another guy asked me out, he compliments me, he always talks to me, he always tries to impress me, etc. He has a good amount of female friends, but he treats me differently (not in a bad way). How can I get him to ask me out? I really like him and I want to try this one more time.