This stitch makes a border
of square "U"'s. By continuing on with successive rows,
you can make a square grid of Straight Stitches, a lovely filling.
The stitching order is as follows : A-B, C-B (a Backstitch), D-C, and so on.
Successive rows make a grid.
Hints:
This stitch must be precise in order to achieve the effect
of a square grid. If you are not stitching on a fabric where
you can count the threads to guide the stitching, then mark
the grid first with a fine, washable fabric marker.