DO start a reference file of inspiring pieces for the room you want to decorate.
DO use jazzy fabrics on pillows and ottomans that can be easily changed out according to season.
DON'T be afraid to use a strong color on the walls. Paint is the least expensive way to totally change a room's appearance.
DO avoid using floral fabrics on sofas—unless you know you'll never tire of it. Try and keep to solids and small geometrics.
DO consider the lighting effects in the room. Will there be an influence of natural light? Will you need ceiling lighting or will lamplight be enough?
DO keep your vision clear—you can be easily seduced in other directions.
DON'T use a rug that's too small—the furniture will appear to hang off of it, making the room appear smaller.
DO beware of scale and proportion and how all the elements come into play.
DON'T forget to break some rules and most importantly to have fun with it!