Choose a mat that contrasts with the color of the art. Generally, you can't go wrong with classic white or cream (trendy colors are a big no-no, unless you don't mind swapping them out every few years). But black and white photos, line drawings and pencil sketches can look striking with a surround of black. Just be sure there's a strong contrast between the art and the mat — a murky piece will disappear in a field of darkness.
