Then paint a thin coat of Mod Podge on one side of the frame and place the squares on top of the glue.
Repeat this over all 4 sides.
Once you get them where you want them, paint a layer of Mod Podge over the the top of the whole frame to seal the squares in place. Let it dry completely.
Add in your picture, attach the backing, and DISPLAY your beautiful Mod Podged frame!
*My squares aren't perfectly even, I know. I like the beauty in imperfection.