Day 21 -This shows Laced Square Herringbone, which was added to Herringbone Square stitch that was featured yesterday.
The live link describes both the stitches in one tutorial.
I used two strands of lilac DMC thread for the lacing.
If you check the stitch link at Pintangle you would find tutorials for many other stitches. All so easy to follow in text and pictures.
1 Year’s stitches can be found here