What is he thinking about? This collage was made with an acrylic painting, topped with patterned papers, and a little more paint added on top. The original was sold and this is a digital print, in which the original was scanned so colors are true to the original. Image measures 9" x 12"; with mat piece is 12" x 18".
Because the piece is odd sized, I recommend a metal "kit" available in craft stores. You buy sides in pairs and have a piece of glass cut. This is much less expensive than custom framing and super easy.