Directions Remove the bottom of a cardboard carton. Cut the fabric several inches larger than the size of the cardboard frame. Miter the corners to fit. Attach the fabric to the cardboard with glue, stretching it to make a smooth surface and attaching the fabric to the outer sides of the cardboard. Decorate any cardboard that remains uncovered by fabric. Let the glue dry before mounting the child’s artwork with thumbtacks. For a permanent frame, glue the artwork directly onto the fabric.