Cut the toe off of the sock, so the toe seam stays with it. Cut the toe piece in half. These will make the arms. Then, cut off the foot of the sock, at the heel line. And, I am sorry about a couple of these pictures, it took me a while to get the hang of shooting them at night (after the children were asleep), but being a visual learner myself, I know there are some of you out there, who would prefer a blurry picture, to no picture at all.
Set the cuff aside for later, and sew up, and stuff the arms, by sewing the length of each toe piece together, turning and stuffing them, and then sewing the ends closed.
With the heel end of the sock body pointing up, cut a slit in the bottom of the piece to form legs.
Sew the legs closed, rounding them to look like the legs of a gingerbread man.
Turn the piece inside out, and stuff it with poly-fil.
With a double thread, stitch a loose basting stitch around the body, midway between the top, and the legs.
Pull the thread tight to gather in the neck. Run an additional row of stitching around the neck, to secure the gather, and tie off. Or, poke the remaining thread through to the shoulder, and use it to sew on an arm.
Sew on the arms by whip stitching both the front, and the back sides of them to the body.
Embroider a face, and close up the head with another gathering stitch along the top edge, just as for the neck. Faces are not my strong point - so I just made two black horizontal stitches for eyes, and one red horizontal stitch for a mouth.