When I first started knitting these socks on two cable needles, I was a bit confused. It seemed a tangled mess. Once I accomplished a few rows, it became clear.
Basically, all the stitches from both cables are pushed towards one side. They are all going in the same direction. I'm right handed, so I pushed all the stitches to the right. The front cable has the free yarn. I needed a needle to knit on, so I took the other end of the cable I was knitting off of. In other words, I put my new stitches right back on the same cable, while ignoring the front cable. Then I turned my work around, and knitted the next row completing the circle. The socks are inside out while knitting. Here they are right side out as they would look when they are worn.