The first thing to do is remove this triangular piece on the bottom side of the thigh.
Next, go find this vein and remove it. Try to pull it out in one piece without cutting it; use a paper towel to help you get a grip. This is the vein that, once in a while, leaves some blood near the bone. You wouldn’t want a judge to find that when he takes a bite!
Now, turn the thigh over and remove the skin.
Trim along the fat lines and remove all the loose and hanging pieces until you have a nice heart shaped piece like this.
Scrape the fat from the underside of the skin using a flat blade. Scrape until you can see the cutting board through the skin, but be careful not to cut through. This take a little practice, but after you get the hang of it, it goes pretty easily and the reward is tender bite through skin that’s never rubbery.
Now put the skin back on the thigh and wrap it under. Your thigh is ready to rub!