The key to a good design is to declare a concept.  Your concept can be anything from a specific theme to a painting.  In essence it is what you want your space to say.  I recently finished a design project for a family who loved beautiful art…..and so we created a wall of art.  We pulled colors from the paintings and incorporated them into the their adjoining rooms with accessories and pillows.  My goal as a designer is to create a space that is a true reflection of the owners.