Every year the main color is green. I try to do something different with the pattern or background. One year it was a map. The next year it was small leafy branches on the outside and oversized leaf shapes on the inside. This year, I chose to add in water drops on blue as the contrasting pattern because so many of our events have a water theme.
Since the raindrops were done in a very structured, geometric way, I edited the leaf pattern to also march in tidy rows. In this way, the two patterns "belong" together.