The key to great-looking readymade frames and family snapshots is matting. Ready-cut mats are available at framing shops, or you can have them custom cut for about $5 to $20 per frame, depending on the size of the frame and the mat's ply (or thickness). A mat serves an aesthetic purpose but is utilitarian as well: It keeps the photo from touching the glass. Otherwise heat and humidity will eventually make the photo stick to the glass, ruining it. Follow these guidelines when selecting mats.

Choose one-, two-, or four-ply mats for ready-made frames (eight-ply mats are usually too thick).

Choose mats that are acid- and lignin-free. (Lignin is a natural substance in wood believed to cause photos and paper to deteriorate.)

To keep the photo from falling through, make sure the opening in the mat is at least 1/8 inch smaller than the photo.

You can "crop" a photo with a mat by centering a small mat opening over only the most important people or elements in the shot.

Attach the photo to the mat by taping it at the top only. This will keep the photo from buckling. (Try Scotch Photo & Document Double-Stick Removable Tape, $5 at craft and office-supply stores.)