This first sock will be the body of the dog. Turn the sock inside out and cut the end off. However much space you cut from the heel will determine how long the legs are. As you see on this sock dog in the picture his legs are going to be pretty long but cutting it closer to the heel of the sock will make little stubby legs that are just as cute.
Now get the other sock and turn it inside out then cut it just like this. The tip of the sock will become the ears, the heel of the other sock will become the head. Again, however close you cut the material will determine the length of his snout and neck. The rest of the sock will become the legs and tail.