The cheapest way of redecorating a room is to paint the walls. Changing the color of the walls simply transforms the space. The only problem is that painting takes some time and creates a lot of disturbance.
So, it only remains one possibility, which is called “accent wall”. The idea is to redecorate one wall using washable paint, wallpaper, paneling or whatever goes through your head. The aspect of your room changes completely within a few hours if you only apply lime or wallpaper.
Choose colors that match the existent ones and create a pleasant contrast with the other walls. In a room with minimalist decor, with little furniture and few decorations you can perfectly use printed wallpaper. But if you have a room with a complicated design, a lot of furniture and printed upholstery, it’s better to paint the wall in one color.