A really easy to do Feng Shui change is making sure the corners inside your apartment are not empty. Why is that important? Any time you see corners that have nothing in them in, it's believed the energy flowing into that area becomes 'stuck.' To help give you a visual, think of water flowing down a gentle stream and then becoming entrapped in a whirlpool movement alongside the bank of the stream.
To help avoid that scenario, adding a plant or a collection of smaller plants (2-3) in the empty corner of your apartment can help the chi' (energy) to keep moving. Of course you could use other objects on the floor (like a standing lamp), along the walls (artwork or shelving) or even something that may hang from the corner's ceiling. Understand the function of the room and combine that observation with the Ba-gua Map life section and you can better select what is appropriate for that corner.