Mat board is used for framing art and photographs. There are three types of mat boards: archival, acid-free, and standard. Within these categories, mats are available in many sizes, colors, and thicknesses. Mat boards have a colored outer surface, a white or cream colored inner ply or layer, and a dull white backside. The inner ply is visible when cut on a bevel. When mat board is not available, there are alternatives you can use.
Cardstock as a Faux Mat
When matting a photo or art smaller than 8 1/2 by 11 inches, you can use 110 weight cardstock. You will need two pieces: one white or cream colored, the other in a color that compliments the photo or art. Trim or cut the colored cardstock to fill the frame's dimensions. Trim or cut the neutral cardstock so that it is just slightly larger than the photo you are framing. Place the colored cardstock faceup. Apply adhesive to the back of the neutral cardstock and center it on the other sheet, pressing firmly. Apply adhesive to the back of the photo, and center it on the other layers. Place in frame.
Faux Mats with Foamcore Board
Depending on the thickness of the frame, foamcore board can be substituted for mat board. Foamcore typically has a colored top ply, an inner white foam ply, and a white back, but some foamcore is colored all the way through. These boards come in large sheets and can be adapted to large projects. Cutting requires a sharp craft knife; dull knives leave ragged edges and loose bits of the inner ply. Chose a board color that goes with the art; trim it to fit the frame; set aside. Trim a piece of neutral card stock just larger than the art and adhere it to the center of the foamcore piece. Adhere art in the center of the cardstock layer and place in frame. For projects larger than 12 by 12 inches, the standard size of scrapbooking papers, use solid colored roll wrapping paper instead of cardstock.
Neutral Foamcore with Colored Cardstock
Neutral foamcore in white or off-white can be cut to the size of the frame you are working with; colored cardstock will serve as the faux bevel edge. Trim or cut the complementary cardstock just larger than the photo.
Matting with Cardboard and Wrapping Paper
For large projects where the frame is too thin for foamcore, you can use a sheet of cardboard and solid colored rolled wrapping paper. Using a craft knife, cut the outer edges so the cardboard will fit the frame. Measure the inside dimensions of your art and cut an interior opening smaller than the art. Cut solid wrapping paper larger than the outer dimensions of the cardboard and place upside down on the work surface. Apply adhesive to the cut cardboard and adhere to the paper. Using a sharp craft knife, trim away the paper that is in the center opening. Place art in the opening and tape in place.