I wasn't clear in my previous post about pressing seams open--sorry, Senior Blonde moment. I join the top 2 sections together then remove the paper from inside the seam lines. Then I press that seam open, do the same for the bottom 2 sections and then the same thing to join top and bottom. This will let the seams stay open--they won't if you leave the paper in the seam lines. Sorry--clear as mud????