Decide on a theme or design motif for your rooms, and choose if you wish this theme to be carried out throughout the house or just in a particular living space. If you are only working on one room or area, be sure to talk to the designer or decorator about how this will work with the other rooms and features of your house, office or space.
Make sure you clearly indicate colors that you like or don't like. Many decorators and designers like to use both neutral and accent colors, and these may not be your favorites. By talking with the designer and clearly indicating what you like or don't like you will end up with a color palette that matches your need.