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.
it is thing wrong with being your self don't follow the gang you were born straight
don't think if you are different from your peers that something is wrong it's not when they go to hell you do not have to follow them be Strong and do what is right God will help you