It's the rare person who has the gay appearance and sends out a gay persona who is not, in fact, gay. And then there are some gays that you would never know unless you know...
My mother's good friend for 40 years is a homosexual man that she met when she returned to college in her 30s. He was a professor at the college she attended, and they struck up a friendship. You'd never know this guy was a homosexual by looking at him or talking to him. No overt effeminate appearance or mannerisms whatsoever.
Speaking of teh gayz, my homosexual cousin just got married last week. He told me point blank at my brother's wedding 5 years ago that he would NEVER get married, and that it wasn't even a topic for consideration, because homosexual men are so promiscuous. I guess legality and a culture shift were enough to change his mind 180º, because his opposition to homosexual marriage when we talked 5 years ago was very logical, articulate, principled, and concrete.
He told me to imagine men and women in a bar, where the women had the same drive and determination as the men to pursue sexual conquest. He said women are in general, the regulators of sex, and that promiscuity generally happens with their consent. But he said that homosexual men have no such regulator. All of them are men on the prowl for sex. For that reason, he staunchly opposed the concept of homosexual marriage for himself, declaring "never". Now, a few years later, he and his boyfriend have married in California.