Allllriiiiiight, give it your best shot..?

It sounds like he likes you still, so I don't think you should have to try too hard to get him to want you back. Just flirt a lot and talk a lot in person. yze - okay nerdy sounding - but just watch his reactions to what you do. Just do some of things that made him like you in the first place. And if you don't like him yet, then don't tease him and don't string him along.