Make your own fabric covered mat

People give me stuff - lots o' mats!

Looka, someone gave me a whole mess of mats!

Sure the colors are no good but I'll show you how to cover a mat with fabric.

If it is double-matted, you don't want that little groove to show so turn mat over and spray BACK side of mat with adhesive. Use glue of your choice. I liked the quick coverage of spray adhesive.

Cut the outside edges with scissors or rotary cutter.

You could wrap fabric to backside but I found that creates a tight fit in some frames.
Make snips on inside of mat.

Pretend you are cutting a pizza and make lots and lots of cuts if mat opening is oval or round. (If rectangular or square, cut an "X".)

Pull fabric to backside of mat and glue. Trim long pieces.

Flip over mat and admire your work!

Place inside your frame. The frayed edges will be hidden.

Here's another: