A fantasy

I am athletic and smooth and clean and have never before been attracted to guys, but after seeing some very well built muscular men at the beach and health club locker room, I am suddenly very curious to know what it would feel like to give a naked massage and oral sex to another guy - IF he has a nice body and is smooth like a woman. I am wondering what is a good position to give head for the first time, and is it easier to swallow if you let him finish and then gulp it down, or to swallow as he is cumming?