This is a variation of the ‘Y’ shaped fly stitch. The series of fly stitch is done horizontally, and here, you overlap the legs of each fly stitch over the other.

You need to know the fly stitch to be able to continue with this tutorial.

plaited_fly_stitch_1      plaited_fly_stitch_2
Fig 1: Begin by making a single fly stitch. After finishing with the tail, bring out the needle just before the second leg of the fly stitch, as shown.       Fig 2: Continue with the process of making fly stitches, but each time, overlaping the tips of the legs of the fly stitches.
Fig 3: A series of plaited fly stitch would look like this.