I gave my daughter and myself a beginner's pack of cyanotype cards for Christmas. Yesterday was a good sunny day to try it out.
I went for foodstuffs and she went for beads. And we both went for the decomposed leaf with its exposed grid, below.
All you have to do is (buy them, then) expose them for something like 20 minutes in the sunlight. Then rinse for a few minutes, and let dry. Beautiful!