HELP A SISTER OUT

sooo, I could use some tips ... I am a girl who’s never been in a relationship before ... and I’m currently crushing on this guys in two of my classes in college and he’s been staring at me for the last 3 weeks. I have NO idea how to spark up a conversation with him in a way that’s natural and doesn’t seem like I INTENTIONALLY came to talk to specifically him. Because it’s clear we’ve been starring at each other there’s no way he doesn’t know! I just don’t know how to go about it!