Colour schemes are very much a matter of personal taste and in the living area will be governed, too, by the aspect, the window area and natural light admitted, and the size and shape of the room.
In general, restful and relaxing colours, patterns and textures are more livable with than brilliance. It is best to confine brilliance to accents in the colour scheme (e.g. scatter cushions) rather than risk it on the background (e.g. wall-coverings or curtains). An effective colour scheme can be confidently devised by adhering to the principle of main colour, contrast and neutral.
You are rarely a free agent. Even if you are moving into a new house, the carpet or the suite of furniture that moves with you may — since they comprise in themselves large areas of colour or pattern — dictate the whole colour scheme.
In a large living area, a colour change can signal the division between the sitting side and dining side almost as effectively as screening. But this should be a subtle gradation rather than a clashing contrast so that there is some unity (e.g. the main colour on the sitting side might be repeated in the accessories on the dining side).
In a small living room storage units may take up every inch of wall space so that the objects displayed make up their own mosaic (e.g. a shelf of books). Where wall space is free, you have a wide choice of materials with which to surface it — from timber cladding to paints and wallpapers. There are several types of wall-covering suitable for walls in a bad condition, including hessian, grass papers, vinyl-coated papers and what the trade calls “donkey’s breakfast”. This is a heavy paper impregnated with straw and wood chips. It can be put on a badly cracked wall and painted over The resultant surface looks rather like rough-cast plaster.
The floor in the living area must withstand a great deal of wear without showing it. Fitted quality carpeting is a worthwhile investment. Alternatively scatter rugs can soften a “hard” flooring of, for example, cushioned vinyl or hardwood blocks.