Kegels involve repeatedly contracting the muscles around your pubic bone and prostate. The purpose is to keep the muscles healthy which in turn will improve your sexual stamina. Kegels by themselves will not enlarge your penis. Other added benefits are a healthier prostate and, in the case of older people, greater bladder control. Some men have also become multi orgasmic by doing them.
The best way to learn how to do kegels is to try to stop peeing in mid stream by clamping down on the muscles in your pubic area. That is a kegel. When you actually do the exercise, however, you do not do it while peeing.
Another way to locate your BC muscle (the muscle which stops the flow of urine) is to flex your penis when you get an erection. The same muscle you flex to move your erect penis up and down is the same one you work when you are doing Kegels.
The great thing about Kegels is that they can be done anywhere with little risk of people noticing. You can do them sitting at work, driving your car, talking on the phone, or any other time.
Like any exercise, when you are starting out, take it easy. Try doing 100 kegels per day to start and gradually increase the number each week until you are doing about 1000 per day. You can experiment by alternating between quick release contractions and holding the contraction for 10 seconds.