Divide the pinwheels into 1/4's and you can see a fence rail pattern with the darker print as the center rail and two lighter strips on either side. ALSO, the lighter strips have a half square triangle at each end, each done in a different color to make up the pinwheel. As you make the blocks, you need to make sure that the pinwheel part in the corner matches the adjacent block to make up the pinwheel, and that they are turned the right way. On one square, the rail is up and down, the next is sideways. At least that is the way I see it!