Step one: buy 2 light and dark fabrics. I bought these last year in Elk Rapids.
Step 2: make lots of these, squares, rail fence, hour glass, half square triangles
Step 3: make 20x 9-patches in the designated colour for the month and trade with the other participants. We did this at our guild meeting each month.
and more strips according to the diagram:
Step 5: arrange in a pleasing fashion:
I think I have kept it sufficiently vague as I do not have the right to publish the instructions for this mystery quilt, but if you think your guild might want to try this mystery quilt contact Cathy at Eagles Wings Quilts. It was a lot of fun, quite a bit of work as completed it will make a full size quilt!