All you can do is ask and let him decide if he wants to tell you. Just like you wouldn't sit in front of someone and watch them make out with their partner (or watch even more intimate acts), you don't need to break into that part of his life. At the end of the day, the most important thing to remember is that his sexuality is his business.
Many turn out to be homophobic, wildly NSFW or just plain not funny. Since it doesn't matter, then you don't have to know, and judging prematurely can only create problems. SeptemEntertainment LGBTQ internet memes can be a mixed bag. This piece of information should not have any impact on how you think of him or how you interact with him. Another important thing to remember is that it's not very important whether or not he's gay.
This is why it's better to ask or just see how things develop between you, rather than just decide for yourself. A good sense of humor is an indispensable tool for keeping you from going insane. Click here to send a condolence to the family of Bonnie Gay, or to share a memory. If you're trying to figure out if your friend is gay because you want to date him (as a woman), it's important to remember that just because he might be interested in men doesn't mean he's not interested in women.