Asymmetrical
Successful basic asymmetrical arrangements have good balance, yet each side is not a mirror image of the other.

That means the items on each side of the center are different, yet are close to being equally weighted, either physically or visually.

For example, a grouping of lightweight items on one side can be balanced by a single heavier item on the other side. Or a lightweight tall grouping on one side can be balanced by a shorter single item or grouping of greater weight or darker colors on the other.

Radial Arrangements
Items swirling around a central point define a radial arrangement. The center item, regardless of shape, is the anchor that allows the items around it to circle pleasantly.

This kind of arrangement has the high visual movement of an asymmetrical design, but it usually best done in a close-to-symmetrical format. It's a pleasant combination of formal and informal elements.

Sizing Mantel Displays
Getting the proportions of items right can be tricky. Consider the size and style of the fireplace, the height to the ceiling above, and the turn of the space -- is it tall or is it wide? Decide what aspects you want to play to: Accentuate the height of a tall room, or downplay it?

Those answers often make the choices pretty clear. And keep in mind that down the road you can always change your mind -- and change the arrangement.

Singular Sensation
Sometimes it's best to resist the urge to overload the mantel.

The most common approach is use a large single item. Mirrors, large art pieces, and wreaths are good choices for single-item mantel decorating.

There is a paradoxical strength in putting just one item on a mantel or over the fireplace: The sense of calm and order this conveys can visually quiet a room because there is just one thing trying to draw one's attention.