Find a demo video on how to skin and portion a chicken on ediblehouston.com
Use a sharp kitchen knife to cut through the skin on one side of the breastbone from the neck down to the end. Gently with your thumbs get under the skin and peel the skin back and around, trying your best to keep it in one piece.
Now the other leg
Turn the chicken over as you go, literally turning all the way around till you get to the other side of the breastbone. Push the skin down on the leg and pull hard to get it over the leg end.
You can even make a small slice around the wings to get the skin off.
If you have done well you will have 1 large strange-looking giant piece of chicken skin.
Want to spatchcock (butterfly) the whole chicken? Use sturdy poultry sheers that cut through the back or breastbone easily.