Depends on your set-up. Turbo cars will launch different than any other combo.. Can of hard to explain but much easier to show. If you come to the Track Day come and get me and I will take you for a run down the track and show you how I do it. Maybe it will help or not.
I moderate the traction with the clutch pedal and the gas. Like I said hard to explain but I actually had to make myself pay attention to how I did to figure it out.