You really can't. Gay men are as varied as heterosexual men and unfortunately many have to hide their sexuality out of fear of persecution. Generally gay men suffer more oppression and have high drug, alcohol, suicide, rates, than other groups. I am not gay but I go out of my way to show love and kindness to gay people I come across and I pray to God that the day will come when people will not have to hide who they are out of fear.
You can't tell. A gay man might let you know he is gay by acting in a stereotypical way, exaggerating his speech and gestures. But if he doesn't do that, then you can't tell.
There is no way to tell. you have to ask him.
Ask him
There are not really many signs to tell you a man is gay. Some gay men do act feminine which is a clear sign.
You flirt back, but tell her you are gay.
A truly gay man won't settle for a woman for long. Time will tell.
Straight men, by definition, do not lean toward being gay. It's impossible. If a man is gay, then he is gay.
You ask them both what their sexual orientations are. That is the only way to tell.
The only way to tell is to ask him.
No, unless they tickle your todger (man on man)
dude what do you mean?
ask him :)