Often you don't have a cord at hand or you want to choose a really suitable color - then you can simply take the trick from Franziska Bünzen from the label "Kuestkind".
She uses our wool weft for this. The photo here in the blog shows the braid sewn on.
Here in the video Franzi shows how she sews the weft.
Quick start Guide:
+ Finish the short side by folding it over and sewing it up
+ then sew along the long edge
+ just before the end, fold the second short side inwards about one cm, then fold the long edge over it and sew the rest of the long edge to the end
Finished. Very beautiful. To be used for everything where cords are needed.