Pick up a dropped stitch in the row below by using a purl stitch or knit stitch. To use a purl stitch to pick up the dropped stitch, find and secure the dropped stitch. Continue working the current row until you reach the secured purl stitch directly below.
Now, with the purl side facing (or if you’re working in garter stitch), pick up the dropped stitch.
Insert the RH needle into the dropped stitch and the yarn strand from the back.
If you can’t readily pick up a dropped stitch from the back or front, pick it up any way you can and put it on the RH needle.
Using the LH needle, pull the stitch over the strand and off the needle.
This step forms a new stitch on the RH needle.
Place the new stitch on the LH needle in the ready-to-work position and purl (or knit, for a garter stitch) as normal.
Check to make sure that you have a bump below the stitch.
