From the book, Easy Decorating Makeovers

Create a collage for flexibility -- it's easy to change items from time to time for a new look.

Limit the number of objects in the collage and arrange them in an irregular pattern for a contemporary look. If you prefer a traditional approach that covers the wall more densely, choose objects that are all the same color; this provides impact without creating chaotic clutter.

Add dimension to the display with items that project from the wall into the space of the room. Brackets, architectural salvage, or wall sculpture add interest by keeping the collage from feeling too flat.

Layer on Style:
Step 1. Centering the largest piece over the sofa creates a balanced composition. Hang it low enough to relate to the furniture. Flanked by a chest of drawers and a low table, the sofa is the axis for the wall display. Molding divides the wall into four panels, which guide the placement of objects. To create a similar effect on unpaneled walls, use the edges of furniture

to suggest imaginary vertical lines that divide the wall space into sections.

Step 2. Add lamps on the end tables. Besides washing the wall with cones of illumination, the lamps introduce verticals that lead the eye upward toward the wall display. They can be different styles and heights and still create formal balance if the shades align at about the same level.

Step 3. Install brackets on each side of the center picture for three-dimensional interest. Place them so they're at about the height of the lampshades but not precisely aligned with them. To avoid stodgy symmetry, place objects of different sizes and shapes on the brackets for a more interesting composition. Hang a medium-sized item, such as an ornate empty frame, high in the left panel to carry the eye to the ceiling.

Varying the size and shape of the items makes a more interesting composition. Fill out the left panel and carry the eye to the ceiling with an ornate, empty frame. Crown the central framed piece with a plaque to serve as punctuation.

Step 4. Define the outside edge of the display with a vertical; otherwise it will feel too loose and open-ended.

Add a pair of paintings in matching frames above the chest, aligning the outside edges with the edge of the chest. These frames define the boundary of the grouping and add vertical emphasis, repeating the vertical lines of the molded paneling on the walls.