There are a number of gay men where I work. Interacting with them at work and observing them interact with others, they have pretty normal male mannerisms and speech. But away from work, observing them in social settings with other gay men, they turn on their effemininity (if there is such a word) in their mannerisms and speech.
I started with the Biomation video and various books on more traditional feminine deportment. It's not that I was interested in being a debutante (necessarily) but understanding what was expected and how to accomplish it. Slowly the instincts changed and something as simple as never standing with parallel feet became normal. I find now I can turn it on and off by changing my mental gender, though it still feels odd to move as Tina when dressed as a guy!