Use graphic wallpaper on one wall to create a feature wall. Large patterns work best on large walls and small patterns works best on small walls. Layer with solids so your space does not look too busy.
To create more interest, mix up your décor choices and avoid the "matchy-matchy" look
Mixing furniture as well as the materials they are made from will give you a unique room
Custom items give you the look you want and add to the uniqueness of the space.
A coat of spray paint can breathe new life to an old piece of furniture you may already own. Consider bright colours for maximum impact.