Sizing: The other testers and I found this pattern to be sized well. Choose one of the recommended fabrics and use the size chart!
Friendly flutter tip: The construction on this part may seem totally counterintuitive. Take deep breaths! Read the instructions. Read them again! Then proceed step by step *carefully* and check the tutorial photos as you go. I kept thinking ‘my flutters are on backwards!’ but they were not. The tutorial really will guide you through it!
Topstitching: I did this on my coverstitch and Judy recommends the WIDE coverstitch because it secures each side of the strap evenly. You totally don’t need a coverstitch, though, a simple zig zag on your sewing machine will do just fine.