What exactly IS happening? I used to have a problem with the Launch Control before. I would do everything necessary: Put it in S, turn off the ESP, Hold the brake, push the gas... and nothing would happen... It felt like I was doing something wrong. It would rev to about 1500 RPMS and it felt like the car was about to move, I figured out it was because my LC wasn't working and what I was essentially doing was pusing the gas and brakes at the same time. That's why It felt like it was trying to move. So I got my transmission reflashed (after some trouble from the service department of my dealership), and my Launch Control worked. Well, after this lengthy story of what was wrong and how i fixed it let me answer your question.
You do everything mentioned, then as you're holding the brake, push on the gas. Your car's RPMs should rise (I don't think it goes much higher than 3,000). It feels like you're in neutral and just revving the engine. But now you let go of the brake and slam on the gas. If you revved it to 3000 your wheels will spin a lot, so I try at about 2000-2500, seems to give me less wheel spin. Then you just tear through the gears. It's a good feeling.