Each section of the tree is a separate square with a different kind of bird in it. It kind of looks like puzzle pieces with only rectangular or square pieces and 'sashing' in between each block. You have to sew it together to make the whole tree with all of the birds in it. Sewing first would help keep the sections straight and help them fit together better than sewing each block apart first and then dealing with stretching, etc. Clear as mud? I hope not!