While my previous chapter focused on the importance of sexual attraction, sadly, that cannot be the only thing your relationship is based on if you desire something long term (believe me, I've tried). Although you very much want to be thought of as a sexual being so you're not automatically and permanently thrown into the 'friend' dumpster, you're not going to get anywhere with an actual relationship unless you become good friends.
There are many different ways to accomplish this. Show them respect, that you care about their opinion. Be there for them if they need someone to talk to. Don't object to late night phone calls when they've broken up with their girlfriend for the eighth time and still can't understand why (in direct relation to this, resist the urge to call them an idiot). Find out what makes them laugh and make them laugh, often.
Most important of all, *listen*. People love talking about themselves. At a fundemental level we're all somewhat selfish and self-absorbed and when someone listens to what we have to say, we find them absolutely fascinating. As a student of the human arts, I know this better than anyone.
One topic of conversation that will inevitably arise from time to time is your sexuality. When that happens make sure to put across that although it's an important part of you, it doesn't define who you are. Defending gay rights is one thing; beating up homophobes wearing a pink shirt and a buzz-cut is quite another.