Cut the four wing pieces (two for each side) to length using a hand saw or miter saw.
Mark a 1-inch grid pattern on one of the wings blank using the template. Use the arc pattern to transfer the arc pattern on the blank (images 1 and 2, below).
Use a jigsaw to cut the pattern. Trace the shape of the arc on the remaining wing piece and cut them to shape (images 3 and 4).
Position two wings with the long and bottom edges flush, clamp in place, and sand to a uniform shape (image 5). Repeat for the other two wings. Keep the wings in these pairs for assembly later.
Cut the long filler strips to length to match the height of the wings (image 1). Cut the short filler strips to match the distance between the bottom outer edge of the wings and the long filler strips.
Apply the finish of your choice to the wings, long filler strips, and short filler strips. We used Cabot Solid Color Acrylic Siding Stain (Evergreen) which acts as a primer/sealer and top coat in one.
After the finish has dried, position the wings and filler strips and attach using glue and #18 x 1-inch galvanized or stainless-steel wire brads.