Room into Studio Closet into Vocal Bth (sketch up included)

Hi everyone, Im desinging my home studio and I wanted to convert an existing room in my house to a recodring studio! I have a sketch up included of the floor plan of the room and I was wondering if anyone was experienced enough to edit the sketch up to include bass traps, studio foam placements, etc. There is also a closet that i drew into the sketch up beacause i would like to turn it into a vocal booth, however, i am inexperienced in the placements of bass traps and which wall to use studio foam on etc. the walls in the room are drywall (sheet rock) with simple texture and paint. The only thickness that I was able to obtain was the wall that seperates the closet and room which is about 4 3/4" thick, i dont know if there is insulation between the wall. Also I'd like to have my Desk on the North side unless is it more benificial for acoustics to have it located else where. help would be appreciated! thank you so much!