This is my cardboard cut out of my foot, with the measurements marked on it. You will use this to determine heel and leg measurements.
My sock on the cardboard cutout, I still have a short distance to go before I have reached the leg line.
I have reached the leg line and now place the lifelines for my leg opening
These are the lifelines in the stitches. You will cut the stitch with the thread loop and unravel the stitches between the lifelines to make the entry for your foot.