How Can You Tell If You A Guy Is Bisexual?

Personally, I think almost if not all men are bisexual. Also, any time a guy can't get it with a woman, and there's a good looking guy around, and they find each other "attractive" to each other in a non-homosexual way, they can still enjoy sex together if it happens. However, think of it this way; a gay man having sex with a woman. He can still enjoy it, it's natural. However, in both cases, it won't feel as satisfying for either the bi-men having sex together or the gay man having sex with a woman. But, some men who call themselves "straight" and interact with other men in sexual ways, are usually bisexual. I had a friend who loved women, however, when I slept over his house, he liked to cuddle next to me and try to touch me. I am a bisexual man myself. I enjoy having sex/cuddling with other men, but, I really enjoy having sex/cuddling with women.

If you are a girl invite him somewhere as friends and where really bare clothing and look at his eyes to see where they are pointing (that's how you know he likes men ) 

I think that most every teenager goes through a period of identity crises. Environmental factors play a large role in s influencing a persons identity as to who, or what they are and where they are going with their life. Each person must decide for themselves what their sexual preferences are and what they feel comfortable with.

My best friend is bi, we enjoy going to the MALL to check out guys together..take him somewhere public and slightly comment about other men.Ask him nonchalant questions that any straight guy wouldn't tell the truth about.

If you heard rumors ask/ I am bi and currently with a girl but she knew ask him?

Well I think when you can see yourself kissing a guy and stuff and you actually enjoy doing that...And you see yourself with a girl also and enjoy that too...Best of luck:)

You cannot just "tell" that someone is a certain sexual orientation.  Assuming usually only gets you into trouble.  If you have known someone for a long time really well you may be able to guess from the way they speak or act.

Just accept people as they are--no matter what label, if any, they choose to associate themselves with.  A label does not define them as a person--after all, they were probably always that way, even before they chose a label to best describe how they feel.

Moo the answerer is right.  Watch his eyes, you'll know who he's into.

Eyes never lie.