The abbreviation mds in knitting means make a double stitch (ds). Double stitches can be used instead of wraps to prevent holes from forming to the turning point when knitting short rows. In this case, the technique is called the german short row.
Steps to make a double stitch:
- After turning your work slip 1 stitch purlwise with yarn in front.
- Bring yarn up, over and back to pull on the slipped stitch until it slides around to show two legs.
- Keep tension and work the next and the following stitches as usual.
How to work the double stitches
Double stitches are treated as one stitch so when you work them you knit or purl the legs of the stitch together.
You can also checkout the video by Purl Soho to see exactly how the double stitches are made and worked.