Your room is where you spend most of your time at, you have to design it according to your personality, this is your personal space. If you love reading, have a book-shelf that is well kept, clean always, line your books, decorate the bookshelf with wallpaper. You can put on a wallpaper on the walls, a design of your choice that is. Some love colored bulbs, some love the bulbs with lanterns.
Lamps come in different designs, they should not be over done, should make a statement in the room. Curtains are not supposed to be boring, play around with different colors and designs. Colors can be monochromatic, curtains, duvet, wall paint and furniture in that room. The bed does not necessarily have to be against the wall, it can be at the center of the room, this applies to a large room.
Closet should not be stuffy, clear out your wardrobe, donate clothes you do not wear, it is easier in keeping the room clean. Plant lovers can have different plants of their choices in their rooms. Add pieces of art to your walls, colors of art are to be the same as the walls, do not color block. Cords should be hidden and not clearly visible by outsiders.