Cut neatly around the wing bone where it attaches to the breast and the ankle of the drumsticks, these should be the only holes in the skin.
Score along the backbone and using your fingers mostly (there is the odd area which needs a little knife work) remvoe the skin in one piece.
Cut one clean line from the back up to each hole in the leg.
On a clean board, using a knife at 90 degrees to the skin, scrape as much fat from the inside of the skin as you can, taking care not to rip or cut the skin, lay each skin carefully onto silicone paper so they don't overlap.
Liberally salt the skins (on the inside), you can now layer up the papers to save a little fridge space. Leave overnight to render off water.
The following morning, rmeove the skins and wash the salt liquid off, discard the paper and dry the skin well.
On a silmat, lay the skin out with minimal overlap trying to achieve one single sheet of skin, repeat with subsequent trays until the skin is used up.
Place another silmat on top and weight it down with a tray and press.
Cook in a 160°C oven until crisp 15-20 mins remove and allow to cool.
Cut to size and when completely cool, store in an airtight container.
This can be done with silicone paper, just be aware as it crisps it takes the paper with it. After 10-15 minutes, before finally crisp, it will need replacing to finish cooking.