Lately, I've been printing by drawing on foam. I'm not sure where I got the foam. I'm not even sure of its original use. It's about 6" x 9" in size and is self-adhesive (a feature not pertinent to this process...).
The hardest part is actually having a design in mind. In this case, I got my design idea from a pillow featured in a Pier 1 Imports ad. As you can see, my owl is lop-sided. When I want a precise image, I will often use tracing paper or deli paper to trace an image. If you use pencil and then turn the deli paper over and go over the image again in pencil....you get a faint image transferred over on the foam. Then, of course, you need to use your ball-point pen to go over the faint image, so there's major indent in the foam.
This process also works well for abstract mark making.
I've even used the process to make faces based on photos.
I also think it's pretty great that, by using 2 Speedball ink colors, I ended up with over a dozen different colors that range anywhere from crimson to a delicate pink and all sorts of shades in-between.