I got Rod's book on Home recording studios, but he didn't go much in depth about the actual design for the CR and iso room(s). It had a lot in it that will help with the acoustic portion of things, but I am totally confused on the room design aspect of things...

I hope y'all can help me get the design figured out. I currently have a 11' x 13' room built with staggered stud walls for my studio room. I am planning on having a control room with an instrument room and maybe a vocal isolation booth too. I know I could always make a temporary vocal isolation booth and get it in there when ever I need it...

Where should I start? Should I go with angled walls in the CR, or keep it square?

Help please...