Actually that's a little easier than if you were a guy. I'll go ask my daughter, who's 25, and hangs out with gay guys a lot because they're so safe for her to be around.
Well, this is what she said: Don't take the risk of exposing romantic feelings to him. When a guy exposes his romantic feelings to YOU and you like him only as a friend, you get all awkward because you don't want to lead him on and be responsible for hurting him with your inevitable rejection, so you start backing off, and your friendship suffers as a result. So the chances are very good that this gay guy would do that to you. So it would hurt your friendship, and neither you nor he would want that. So you need to just enjoy feeling romantic about him and not act on that while you wait for your feelings to subside.
He probably can feel how much warmth you have for him, so it's a very precious relationship for him as well as for you. That makes it a great Platonic friendship--where both of you can learn from each other, as long as you control your sexual/romantic urges so your feelings lead you to aspire to emulate each other's virtuous character traits--and thus you are "sublimating your love" for each other.
The other issue your feelings bring up is "what's going on with you and heterosexual guys?" I'm guessing your age is 21 or younger, and you might be repeatedly bruised emotionally by the immaturity of young teenage&twentysomething boys, because you're highly sensitive. Look up the Highly Sensitive Person self-test by Elaine Aron and read all about it, because that might help you understand if it's true that a gay guy with more prominent feminine personality characteristics is more comfortable for you than an immature male who's not able to empathize with your sensitivity.
Please feel free to respond and I'll discuss more if you want.