I take the air intake off at the throttle body, unplug the MAF sensor or the car will not run. start the car and spray directly into the throttle body making sure to hit all the dirty spots. if the car tries to die stop for a second then finish spraying the whole can. as soon as the can is empty turn the car off. put air intake back on and plug the MAF sensor back in. let the car sit for a few min, the can will tell you how long. then simply start the car back up and let it run untill it don't smoke any more. "it will smoke like crazy for a min or two" then your done. these instructions are on the back of the can also.
There is not much to mess up its pretty simple. and this stuff works great i have used it in the past with other cars. i just wanted to make sure it was OK to use with our LS motors and it looks like its OK from what i hear. no problem yet at least lol. GM did this to my moms cadillac, and charged her about $80.00. it takes 5 min to do and is so easy, and if you order it from Greg "two-tons-of-fun" its only $10.36. can beat that