The day before you plan to cook and eat it, coat the inside and outside of the turkey with the salt. The more salt that adheres to the meat and skin, the better.
Leave the bird uncovered in the fridge overnight—the dry air helps remove moisture from the skin so it can crisp up in the oven. It will turn translucent and almost waxy.
An hour or so before you roast it, rinse off the excess salt, then pat the turkey dry. Cover the outside, especially the breast, with soft butter and pepper. Place on a roasting rack breast side up, above a roasting pan.
Put 1 quart of water in the bottom of the pan to create more liquid for making gravy afterwards. Roast at 425° for half an hour, then turn down the oven to 375° and continue until the thigh joint registers 165° (not 180°, like the USDA used to say.)
A 12-pound turkey will take about 2 hours and 45 minutes total.
Let the turkey rest for 15–20 minutes before carving.