The shell hem is not a hem as much as it's a decorative technique that can be added to edges. It describes when parts of the fabric are pulled inward giving the effect of a scalloped or shell edge, hence the name. It's so pretty and delicate and a great thing to add to those garments when you want to add a sweet detail such as to baby and kid clothing or even to your own. The best part is that it's an easy technique to pull off and can be done easily using your sewing machine and a specific stitch. For best results, I found that the sewing machine shell hem tends to work better on knit fabric. If you want to do it on woven, you might want to do it by hand instead. But give it a try, just realize it should be done to an edge that's already hemmed, like necklines, sleeve hems, and bottom hems, and can be done on garments you've made or added to ones you've purchased. Have fun with the shell hem.
Shell Hem – Sewing Machine Stitch