5 - Buy a Plant
Surrounding myself with green in the winter makes me feel a ton better! If you consider yourself a plant killer with no green thumb, someone at your local plant shop or greenhouse can point you to some varieties that are super hard to kill. (Snake plants, spider plants, and pothos are great ones to start with!)
For a free option, ask a plant-loving friend for a clipping of one of theirs that you can stick in water!