By using light curtains, allow more light to enter the living room area. Instead of using heavy looking "valances" use simple and easy if possible semi transparent curtains that are ample to reduce glare that might be caused because of sunlight. Use brighter color schemes commonly known as "hot" color schemes. These create a very good reflection and transmission of natural as well as artificial light inside the living room. There may be one more different procedure for defining the perception of the living room (or any interior space) and that's the empty volume left behind after all the furniture as well as other accessories have been fitted. Because anything in your living world is usually "relative". The perceived volume is always relative to the empty volume which is normally used for circulation. The more empty volume you get, the bigger the room will look.