I did a little experimenting when I was illustrating a book cover. I bought a fern and used a stem of it to create a watercolor version of it. I brushed the one side of the leaf with red watercolor and pressed it on the watercolor paper, twice. The fuller version was the first “lay down” and the starker version of the leaf is the second “lay down.” Before I applied the watercolor I made a drawing of the leaf. Put all three versions in Photoshop and put them through filters.