So you have knitted most of your sock, now time to knit a heel! Place the stitches above and below your scrap yarn back on your needles as follows:
Step 1: Start with the leg of the sock away from you and work from right to left. Beginning at the right edge, insert your needle under the right leg of each stitch in the row below the scrap yarn, until you have picked up one stitch for every stitch you knit with your scrap yarn.
Step 2: Now turn your work upside down, and insert your needle under the right leg of each stitch as in step 1.
Step 3: Turn your work again, now you can remove the scrap yarn completely.
Step 4: Once the scrap yarn is removed you can begin working your heel - turn a tube into a sock!
You'll be needing this technique for Pom projects such as: