If I had to decorate a cubicle these days I would take inspiration from those people who have been making Post It pictures in the windows of office buildings.
It's actually quite amazing what kind of pictures can be made with simple squares of paper.
I'd use the mini Post Its, since it will be a smaller space, and make sure that the office manager knows what you're doing and that you're using your own supplies and not raiding the office (since your handiwork will be quite obvious!).
I'd also look for other cubicle decorating ideas online. I'm sure there are whole websites dedicated to the amazing things you can do with such a small and bland space.