My crush sits next to me in class now, what do I say or do now?

askmepleaseme
So we recently got free seating rather than arranged and he sat next to me with his friends on his other side. He could have chosen to go to the other end of the class where there were a bunch of empty seats, and his friend was going there until he said he'd rather stay on "this side", but maybe I'm overthinking that part. I had a feeling he was attracted to me from that start, but I'm not totally sure now. I think I've made a few bad impressions. At first he sat next to me when he first met me, would stretch and lean back his chair and I noticed him staring from the corner of my eye, was excited I'd be in one of his classes, but nothing interesting has happened since.

Now this is the perfect opportunity to talk to him. But what do I say? Where do I start? I'm pretty obvious I believe when it comes to these things and his friends would be watching and listening to everything I say to my crush intently. I feel a bit awkward around a group of guys. Also, when I'm interested in a guy I tend to act very cold and unassuming towards him. It's almost off in a way, and it totally gives off the vibe of being turned off, which I can see why guys might think I'm rejecting their advances. I'm just super inexperienced (sex, dating, opposite gender) and it comes off stiff and strict when I'm really into someone. I feel like if I'm too eager, it's going to be way too much/obnoxious/or really obvious to those around us.
My crush sits next to me in class now, what do I say or do now?
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