This great little technique can be used to add sections of color designs to stockinette. (It reminds me of cross stitching.) Many knitters use the Duplicate Stitch in lieu of small areas of Intarsia. These added stitches are placed on top of stockinette stitches after the piece is complete with the use of a tapestry needle. The Duplicate Stitch is also a great way to cover errors and wonky stitches you wish you had discovered prior to binding off. I especially love to use the Duplicate Stitch when weaving in ends on the right side of the work is needed.
Every knitted piece will have at least two ends, or “tails” to weave in at the completion of the project. It is especially nice to weave the ends in invisibly to give your knitting that professional touch. This video demonstrates how to do this on the wrong (purl) side of stockinette knitting. If your knitting is in a different pattern, simply follow along the path of one thread of yarn in the same manner as the video demonstrates. It really is quite simple and worth the few extra minutes it takes to do.