When framing art, you should first think about how it will make the art look better. It can make the difference between enhancing the art or killing the art. You want to draw the observer’s eye into the art without overpowering or competing with the art.
Secondly, you need to understand what you are framing and how to preserve the art if needed. Most damage to art is due to improper framing. You can always fix a presentation mistake, however if the art needs to be preserved, mistakes in frame may cause permanent damage.
Mats can separate the art surface from the glass. This creates an air gap which helps keep mold and mildew from forming.
Mats can provide a visual background; wider mats may work better by creating more focus on the art. However you need to consider the color as well. You don’t want to overpower the art.
Choosing and coordinating colors with the art as well as the room the art will be displayed is a good place to start. You can emphasize specific colors found in the art and colors that will coordinate with the room. However; Its a good idea to keep the colors more neutral so as your room décor changes over time the art is timeless.