I will have to admit you will not be able to do this on the first try. Trust me, it took me a while to do. Here's what you do: jerk off the way you prefer, no matter how you do it. Once you come, don't stop jerking until you cum a second time. At first it will hurt. But once you get through that, your second orgasm will be intense. And I mean intense as hell. Your arm will be tired but it'll be worth it... easier to do on days where you feel really horny.
The first time I was able to do both stages I felt like I could die now and be happy