Make a foundation chain of the required length, or work row 1 directly into the item to be trimmed with right side facing.
(multiple of 6 stitches + 3)
Row 1: 1 ch, 1 sc in each chain to end, turn.
Row 2: 3 ch, 2 dc, *3 ch, skip 3 sts, 3 dc, repeat from * to end, turn.
Row 3: As row 1. Fasten off.
Fringe: Using a single length of yarn, make two knots around row 3 in each 3-ch space.