On a recent visit with some of my nieces and nephews in the US, I was looking for a quick craft project to do with them. Then I spied some styrofoam trays about to go into the garbage, horrors of horrors, so I rescued them and spent half an hour or so teaching the art of printing!
The most important tip for this project is to keep the designs very simple, and to make sure that the paint is neither too thick or too thin. It may take a few tries to get a nice print, but it's worth it. And in any case, you can always cut apart your prints and collage the best results together. (Which is what I did with the blue Chamsa shape below.) And it's important to remember that part of the beauty of this project is the imperfect results! For complete instructions, and some more techniques, see my post from last year here.
Oh and by the way, Rosh HaShana is just a bit more than three weeks away, so how about using this technique to make some unique cards to send to relatives and friends? And if you make prints on water color paper, or card stock, you can also go over your prints with a light wash of color, which can look gorgeous!