Take a length of around 13" of wool and untwist it so that you have the strands as pictured. Wool varies and can have anything from two to five strands twisted together to make up one length of wool. Catch in two or three untwisted lengths at the hook bend as shown.
Return the thread to the eye. Now build up a body by winding the wool strands back and forth along the hookshank. Make sure that you finish at the eye and have around 2 inches of length left over. Do not trim this length.
Catch in the thread again where we first started. Pull the excess wool backwards and make sure that it lies flat and tight along the top of the body. Secure with thread, whip finish and cut away the thread. Pull the lengths of wool together that are now acting as the tail and trim to length.
If you need to add a different colour back, then before you wind the wool (Step 3). Catch in two strands of untwisted coloured wool and leave its length over the eye. Then create the body as usual and the rest of the procedure is the same. Here's a white baby doll with a Green Back.