I usually work on these in pairs that could be purchased together or individually.
I use Faber-Castell Pitt Markers over the Mod Podge to paint in my ladies. You could also use, paper dolls or prima stamp sets to add your figure...or use flowers, butterflies and such as your focus.
Paint the sides of a little canvas and adhere you square on top, you may want to trim slightly by a 16th of an inch or so. I often let ephemera hang over the sides that I can wrap down and over the sides adhering with gel medium.