Start with a sharp fillet knife. To mantain the largest possible piece you need to leave one edge intact. Start a cut at the base of the tail at an edge. Go straight up the edge, over the and around the end of the tail and stop the cut at the end of the curve. The actual leather hide you're wanting in the end is thicker at the base of the tail than at the tip. If you have a rounder tipped knife use it to skin the hide from the tail. If you crudly get the bulk of the fat and tail bone out at first you will soon be able to lay the tail out flat. With the tail flat you can scape the rest of the fat off with a spoon. When you start seeing the dark hide take it easy so as not to rip the hide.
If you want you can salt the tail to draw off moisture and lightly scape again. Now you should have a clean piece of leather. Wash it in dish soap a couple of times and it's ready to apple as a handle. If you want it soft you'll have to tan it.
Hope this helps