Consider what the room is used for; some people prefer casual spaces to formal, and some people like to entertain friends while others do not. To anchor the room, incorporate a focal point such as a fireplace or artwork, and try to avoid creating an overly formal atmosphere.
Bring flexibility into the family room with modular furniture that is easy to move and store. Small seating provides options for a number of people, while items such as ottomans are easy to stow when they are not needed.
Using a rich color on the walls creates an intimate and inviting atmosphere in the room, although if the family room is connected to a kitchen or dining room, consider matching the color schemes for a sense of continuity.