My T didn't have her own office. However, wherever we were, I always had trouble with looking at things so I got to where I'd deliberately do stuff. I started with my chair; it was a La-Z-Boy-type to recline but was pushed all the way into a corner (so it wouldn't) so I deliberately would pull it out some before we started our session. I messed with the box of tissues and moved the clock; it was so T could see it from her seat but I made it so both of us could see it. I sometimes brought in "props" like my grandmother's afghan comforter in winter and wore bedroom slippers in a couple times; took over the room, made it "mine". I wrote a poem about the set of elephant figurines
http://www.squidoo.com/elephants-figurines in the bookcase and, when we used the director's office, I looked over his books (sniffed in disinterest like mine were better :-)