In the control room you'll want to put it on the wall your monitors face, as to kill reflections. On the side walls, use the mirror technique to see where you need the foam (sit where you will when you mix, have a friend move a mirror around on the walls, anywhere you see the monitors in the reflection is a potential spot for the sound to be reflected back at your ears and create a reverberation you may not notice is not actually in the recording.)
In the tracking area, I just put my foam up enough to kill all the reverb. You have large sheets so it won't be hard to cover most of a wall and kill the reverb. Unless of course the room sounds pretty good already with it's natural 'verb, in which case, put up some bass traps and call it a day.
"How you gonna drink yo Vodka!?" - Jason
"Pre-CBS Fender corporate buy-out."
"I'd raise the bridge, file down the nut, and take the buzz out the low E."
"God, I love this woman."