Our daughter's nickname is Moe so the idea of turning her into the "Mo"na Lisa for Halloween seemed like a natural fit.
Step 1: The Foam Finger
To start with we used 1" green foam to create a large envelope for our daughter to fit into. The locations for the holes for the face and arms were based on the painting. We found a high res image of the painting online and printed a copy onto canvas. Using this we traced the face and arm locations (at the elbow) and cut them out.
Step 2: Wrap the Envelope
With the holes cut, we wrapped the foam in the printed canvas. First we took a piece of blank canvas and covered the back and edges of the envelope. Then we took the canvas printed with the painting and glued it to the front of the envelope cutting it flush with the edge of the foam.
Step 3: Adding 3D Details
To blend the painting elements to the dimensional costume pieces we covered the dress in the painting with the fabric we chose to use for her skirt and added trim to finish it off.
Fake hair and a bit of a veil around the face hole helped mask the edges of the opening.
When finished, the effect was that of a fully costumed, Mona Lisa standing in front of the painted background.
Step 4: The Frame and Back
The picture frame was created in a manner similar to the painting itself. We built a green foam square sized to sit on and slightly overlap the envelope. We then printed an image of the painting's frame and glued and wrapped it around the frame square. This was then glued to the front of the painting.
To provide a little detail to the back of the costume which would otherwise be a large blank, we added a little picture-hanging wire. Obviously, this wouldn't be what the actual painting looks like but it helped sell the idea of the painting.
Lastly, we printed a replica of the info card from the Louvre found next to the painting and attached it to hang off the side of the costume.