An easy and most decorative hand-sewing hemming technique for fabric edges that will be on show, for particularly fine, springy weaves or cloth that is simply too delicate to put through a sewing machine; use also for lampshades, dressing table skirts, etc.
The hem must be as narrow as it can be – finger rolled over twice and pinned or held so that the raw edge stays inside; you then work an over stitch at right angles to the hem every few millimetres or up to a centimetre, secure it, then holding the hem between your fingers, pull the thread so that it gathers a little and forms a scallop, or shell shape.