Sketch your great room floor plan with a pencil and paper. Mark areas on the floor plan to designate furniture placement. Group furniture together to create two sections.
Use area rugs to define separate sections. Choose two separate colors to define both areas. Alternately, place an area rug on one side only. Leave the other side of the great room as is.
Place a sofa against the wall to ensure space in the middle of the room. For an opposite effect, use the sofa as a divider. Place the sofa along the perimeter of the sitting area, with the back of the sofa facing the opposite side of your great room.
Place a dining room table, parallel to the sofa, on the other side of the room. Place large furniture, such as a pool table for a game room or a desk for an office, in the same direction as the sofa to create fluidity in the room.
Use a bookcase as a divider. Choose one or more bookcases that are open on both sides to create a division between the two areas.
Use potted plants to create a visual border. Imagine a line that divides the great room in half. Place tall potted plants against the wall, on each side of that imaginary line.