Please help! Boy troubles!?

so im 15 and i went out with this guy a few years ago but it was kinda awkward and we didn't really talk... and we haven't really spoken much since then until recently... and now i talk to him quite a lot and i am starting to like him again and he is really nice but i don't know if he still likes me because he has had a few girl friends since we went out and i don't know if hes interested anymore or whether he just likes me as a friend... how can i tell if he likes me more, how can i show him im interested very subtly and how can i get him? any suggestions will be great thank you!