I need ideas to use in an apartment.

You could buy bed sheets or table clothes and tack up on walls for color in a room, at least on one wall. For shelves, you could lean an old ladder against a wall or use an open ladder and use boards running from one step to the one across from it for the shelves.

Bookcases and bakers racks are inexpensive at yard sales etc and can be painted easily

Shelving with wallpaper on the back of each shelf space in your favorite/coordinating colors, large paintings (they could be shower curtains mounted on a frame), have color in your furniture, drapes. Have fun making it your own.

Wal-mart has some vinyl "sayings" in the paint department that are anything from Kids designs to religious they can make a room feel good! Very cheap too.

But you can use those command hooks and hang chains attached to shelving. Or go to your thrift store and get a large frame and put a really nice piece of wallpaper or maybe there is some really nice wrapping paper you like. On YouTube There are some nice items to fit from the dollar store or dollar tree.

You could make your own abstract art using colours from curtains, pillows or rug. Just buy a big canvas and chose a pattern: spatter paint, ombre stripes, circles, random, brush strokes. Just lean it or use command strips.

https://lollyjane.com/diy-abstract-wall-art/

https://www.buzzfeed.com/stephaniefisher/22-ways-to-pretend-youre-an-artist-xgub?utm_term=.oa0NK1Q0p#.padPRXdeK