I used a mosquito-screen from a window, some dirt, a piece of wood for squeegee, and the stencil was made from matt-board.
The stencil and the design is inspired by the crop-circle phenomenon in Europe and around the world. The crop-circles can be very complex and beautiful with geometric shapes. This phenomenon was brought to the bigscreen with Signs, with Mel Gibson. You can go to cropcircleconnector.com and look at some photos & info.