The right thing to do after being assigned a cubicle is to abstain from any design on it. It is already a synergistic perfection of brutalist minimalism.
Second best is to be jovial, putting up your favorite cartoons and other light whimsical decorations until you cross the line and receive a warning from management.
The worst is to put up images of your hopes and dreams to remind you throughout the day of what you are missing and wish to experience one day in the infinite future you keep putting off. Your hopes and dreams will likely never come true because you have settled for trading your life to spend every day in a silly office obeying email and demeaning tasks. Tormenting yourself for years with pictures of joyful living is a masochistic exercise in self-flagellation.
One of my co-workers has a cubicle filled with pictures of houses that she dreams of. None of them suggest any particular theme of preference. There is a mountain home and a beach home and a brick home and a 1930s Spanish villa. She simply dreams of having a nice home in a pleasant location that she will never ever have. Sad.
It is good to have dreams, but our dreams must be realistic and accompanied by a considered plan that our work gradually takes us closer to achieving. Teasing oneself with pictures of wealth that will never come from a cubicle job is just cruelty. Better to mock the workplace and remain spiritually free if you can disconnect from it all.
A sober look at what results from our effort is a realistic vantage point for considering the type of future we are creating for ourselves. Everything else is willful deception, which makes you complicit in lying about the nature of the world.
No employer cares about your life or will help. You can get some money from them for a while, but everything significant must be achieved on your own. You need not broadcast your deprivation and silly dreams to other tortured coworkers who are already suffering plenty.
Most of all do not mislead yourself or soothe your emptiness with pictures of lifestyles beyond your means.