Butcher duck into its separate parts (2 legs, 2 breasts, 2 thighs, etc.).
Remove all of the skin, except for skin on the breasts. On each breast, leave a layer of skin about the same size as the breast. Reserve all of the skin and fat. Salt duck parts liberally. (Alternatively, you could brine...See Brining recipe)
Reserve all of the excess bones (i.e., backbone, etc.) for stock (either use now or freeze).
Preheat oven to 200F
Place all of the skin and fat into a 2 qt dutch oven (Le Creuset, Staub or other heavy pot that can go on the stove top or in the oven)
Cook fat/skin over medium low heat until melted into oil with only crispy pieces of skin left in the melted fat/oil. When the crispy pieces won't cook down any more, remove the crispy pieces and discard or keep if you can find a use.
Place all of butchered duck parts (other than pure bones for stock) into the dutch oven with the duck fat. Make sure all of the duck parts are fully submerged in duck fat. With regular american ducks, the breasts are very skinny. You can keep them separate and pan sear, roast, etc. or just confit with the rest of the duck parts. It's up to you.
Place dutch oven in the oven uncovered and cook for 6 to 8 hours
Remove from oven and let the dutch oven sit on the counter until duck and duck fat has cooled (at least an hour).
You can either pick all of the meat off of the bones (which I've done for the sandwich in the picture above) or leave on the bones. I prefer to pick the meat off of the bones.
Place duck meat submerged in duck fat in a tupperware/rubbermaid and put in the refrigerator. Duck meat will last for several weeks submerged in duck fat.
Use duck meat in recipes that call for duck confit (like my Duck Confit, Carmelized Onion and Gruyere Sandwich recipe).