If you are a young guy, and having fairly infrequent sex, try jacking off sometime before the main event to take the edge off. I would also say to try not to anticipate things too much, i.e. don’t sit around all day fantasizing extensively about how you are about to have sex. You can get yourself overexcited which will lead to premature ejaculation. I know we all think about sex many times a day, but don’t just sit there staring off into the distance in a detailed fantasy. It’s fun, but in these cases it can be too much. At that point do something to take your mind off of things.
During the main event, it is tough to keep the right balance. I really don’t like the idea of trying to think of something entirely different, I think it takes away from the enjoyment. Premature ejaculation comes from over-excitement, over stimulation. Try this: instead of being a giggly schoolboy, thinking to yourself “My God, I’m actually having SEX!!!”, try to develop a more self confident inner voice…like “yeah, baby, how do you like THAT! Who’s your Daddy?” Concentrate not on how it feels for you, but what you are doing for your partner. Disconnect yourself from the sensations on your dick, work to convince yourself that they are not that important at the moment. Do anything you can to lower the importance you attach to having your dick in a girl.
In sex, there is a time to give pleasure, and a time to receive pleasure. My motto is “Ladies First”, mainly because I know I am a selfish bastard and my interest in doing anything for her goes down dramatically after I cum, at least for 30 minutes or so. Sad but true. If we work it into some simultaneous thing, great.