What are some good tips to get a guy who's partially interested to being totally interested?

I'm a cute, fun, charasmatic girl. But I'm also a tomboy, straightforward, and really just "one of the guys". When I date the guy usually thinks I'm attractive and that I'm really cool but they aren't interested enough to date me or persue any possiblity of further dating or being in a relationship. So I'm just wondering if there are any tips or tricks to get him more interested in me? Also any tips on flirting would be helpful as well. Thanks =)