The first thing you have to do to find colour harmony is to find the KEY colour, that is the largest colour in the room that you can’t change. For instance you have a blue bathtub and you just can’t change it but you want a more modern look. Blue is the KEY colour. From there you can work out the colours that harmonize and communicate the style and mood you want to have. Use a colour computer, from any art store, to work out the combinations of colors that could work. Choose the colour scheme that best conveys the mood you want.