To create the swirly and linear designs that you see above, I cut fun foam with inexpensive pinking shears. I made the small squares border by cutting into the foam. For the circles design, I used a drafting template.
Here is a photo of the actual foam tools that I made. After each pass that I made on the plate, I wiped the excess acrylic paint off the foam to achieve a sharp design. When I make new tools, I plan to glue two foam sheets together, before cutting designs, to give some weight to the tools.
For the right-hand print, I used a detailed stencil. So far, I've found that stencils with larger openings produce sharper designs.Usually when I'm done with printing - and have already cleaned up the paint and plate, I begin getting new ideas for stencils/masks and substrates. Today, I wrote those ideas down so that I'll be ready for my next printing session.