It's greek (Russian) to me; Maybe do it in seed stitch?
Tea Rose Home New Years ReSewLution - The Sewing Rabbit - upcycled Sweater Refashion tutorial.
Планки "в подгиб"
Cables using i-cord video (Diana Sullivan)
Школа машинного вязания | вязание на МАШИНЕ. | Постила
How to use ribber cast on comb when knitting folded hem. Picture tutorial as I can't read Russian, but the idea is clear.