Additional options: A quilting guide can be helpful for spacing rows of decorative stitches. Also appliqué scissors are specially designed for trimming up to the edge of a satin-style stitch like this.
This is very cool and turned out beautifully! I wonder if you could do something similar on a serger, disengaging the blade and doing a rolled hem. But the inside of the scallops might be tricky. Any thoughts??
an idea for upcycled jeans - keep the top part, cut off just below the back pockets, then add other fabric gathered and stitched to the top (maybe 2 tiers) and then finish with a scallop hem for a casual somewhat boho look. What do you do when you run out of bobbin, as I'm prone to do?