What's the best way to grab a guys attention that you like, but he is infatuated with someone else that doesn't like them?

This is kind of a confusing question but I will clarify it…

I like a guy that I just met at the beginning of the summer, and I’ve been talking to him a bit more. My only problem is the fact that he really likes someone else, but that person that he likes does not like him back.

I really like this guy, and I kind of want him to notice me as more than just a friend…

What would you suggest to be able to help me to grab his attention and notice me in a different (good) light?