Maybe I'm a little naive. Don't think I would be able to pick up on subtle gestures that a gay man is hitting on me. Any help is appreciated.
If you're not having a conversation, then lingering looks into your eyes could be a sign that he's sexually interested in you. But sometimes it's coming from his subconscious, if he's still in the closet to himself, and he's not even consciously aware of his attraction and desires towards you. So you have to tread carefully. Stare back, and smile. If he smiles back during a long stare into your eyes, try to start a conversation. During the conversation, if he, for example, touches your leg or arm multiple times, even in a nonsexual way, is probably him sexually flirting with you, even if he otherwise is acting totally straight (you know, showing no gay affectations). You can mention how you're just not having any luck with women these days, and see how he responds. You can even say something like, "God, sometimes I just wish that I was gay, because they seem to get a lot of action." See how he responds to that! It's tough having gay desires and wishes in a "straight" world filled with homophobia. But you've got to live your truth, whether it's bisexuality or homosexuality. You'd be surprised how many men out there are bicurious, bisexual or gay. Just reading the posts in this forum in the bisexual sections can give you an idea of how prevalent it is. It's the most natural thing in the world for two men to have sex together, whether oral only or anal too. Totally natural, and so much fun!