I wonder if you could insert scrap pieces of graduating sizes to smaller around the edge and the facing like one would edge a garment with rick rack, but using scraps.
https://weallsew.com/how-to-sew-rick-rack-trim/ I'm thinking scraps that are pinked or fringed would give the impression of the roughness around the edges.
There is a youtube video for facing an uneven edge.
https://www.youtube.com/watch?v=A1LhcyyTXSk I'm thinking you would not to do it the way in the video, but probably could. I am remembering how to sew a scalloped hem by sewing a straight piece (facing) over the skirt sewing the scallop and then trim and turn. I think that one could do that with points or almost any shape you wanted.
Janey - Neat people never make the exciting discoveries I do.
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