With RS facing, slide the needle into the stitches on WY so that your needle tip is at the edge you will beg working from. Be sure to have the right leg of each stitch to the front of the needle. Remove WY. If working from right to left, go into the stitches as to purl; if working from left to right, go into the stitches as if to knit.
See also: Waste Yarn in Place of Stitch Holders