I open up the back, pull off the black backer board (usually in many chunks) and then take out the foam core center. I then gently open up the artwork like a present to lay all the edges flat. If you have box cutters and a cutting mat, then you have everything you need to make that art canvas lie flat for framing without a mat. As you open up the back, you’ll see the beveled edge on the inside that makes the corners so nice and flat when it's folded up. No ruler needed, you just run your knife along that inside beveled edge and it cuts perfectly to size.
Make my art, YOUR art by customizing it to get the designer look you want!