To work the crochet hook and scrap yarn method, start with a crochet hook about the same size as the knitting needle you’ll be using for your project. Begin by making a crochet chain one or two stitches more than the number of stitches to be cast on for the pattern you are working. If the edge is to be decorative or removed to work in the opposite direction then the chain should be made with a contrasting color.
Continue to work the pattern as given in the instructions. Some instructions indicate that the provisional cast-on be removed so the piece can be worked in the opposite direction. In this case, hold the work with the cast-on edge at the top. Undo one loop of the crochet chain, inserting the knitting needle into the stitch below the chain. (This stitch is on the original first row of your knitting.)