Ferns work really well.Take the cardboard from a new dress shirt,and spray paint a fern using the cardboard as a backer.Let dry,remove the leaf or fern throw it away.Cut out the Cardboard negative,but save it.Save your cardboard leaf and the board you cut it out of [the form].Spray a solid earth color over the stock use the ''leaf'' or part that you cut out where ever you want the base color [earth] to show through your new color [foliage green]and the ''form'' [peice of cardboard you cut your leaf out of ] whereever you want your ''cover'' [foliage green] color to show.