Use symmetrical or asymmetrical arrangements of art to create either a formal or a casual feeling.

Symmetry simply means that when an arrangement is divided in half, each half is a mirror image of the other.
 
Symmetrical Arrangements

Symmetry adds balance and formality to an arrangement and is generally pleasing and calming to the observer.

Asymmetrical Arrangements

Do something unexpected by hanging pictures in an asymmetricl arrangement. This eye-catching grouping is a casual fun look for informal settings.