I used a 3/4" piece of foam that I cut in half. Using painters tape on the back side I made a hinge so the board could fold up. Next I printed out a Chaos symbol that I got from the Internet. I taped it down to the board.
Next I used a sharp sculpting tool to poke the patter into the foam. BTW - this is the same technique to carve pumpkins.
I then connected the punch marks with a pen.
I used a Hot Wire Foam Factory tool to carve in the symbol.
This is what the finished symbol looked like.
Here is the boar with a couple of hills int he corners to position the obligatory war machines.
Next I covered the board in sand.
Finally, I based coated the board followed by a simple dry brush and voila it was done. For added strength the board is sized to drop onto a cork board that Andy was bringing to the event.
As advertised the board folds up to fit into my suitcase.