Add Bag Sides
1. Fuse an interfacing D rectangle to wrong side of each black stripe D rectangle.
2. Using Corner Cutting Pattern, mark curved cutting line on bottom corners of both interfaced D rectangles (Diagram 9). Trim along lines to round corners and make side panel pieces. Fold each side panel in half lengthwise; mark bottom center with a pin and unfold.
3. Matching bag center bottom seam and a side panel bottom center, join pieces, easing bag center around rounded corners of side panel and securing tabs on interfacing in seam (Diagram 10). Repeat with opposite bag center edges and remaining side panel to make bag body.
4. Turn and press top edge of bag body 1/2" to wrong side. Turn bag body right side out.