One common shape that sometimes presents a challenge to appliquers is the valley (aka: reverse point, or inside corner). We thought it would help if you could see these areas with x-ray vision, of sorts. Nancy stitched these samples using silk organza (quite a different challenge!) so you could see what the turn-under allowance looks like.
Now, take two pieces of fabric, cut a few valleys and stitch them for practice. We think seeing what is happening with the turn-under, following our methods, and a little practice will increase your confidence, making you proud of your reverse points.