In a small bowl, combine the salt, rosemary, and lemon zest. Remove the neck and giblets from the turkey and discard or keep for gravy. With paper towels, pat very dry (you do not need to rinse the turkey; this has a greater chance of spreading bacteria than removing it). Transfer the turkey to a rimmed baking sheet or shallow baking pan. Sprinkle 1 tablespoon of the salt mixture inside the cavity.

Rub the rest all over the outside of the turkey, including under the wings and the legs, and concentrating especially on the breast (no need to salt the very backside of the bird that is touching the pan).

Cover tightly with plastic wrap. Refrigerate for 24 to 48 hours, until either the day before or morning of cooking the turkey (the length will depend upon how early you started.)

1 Day Before or the Morning of Cooking – Let the Skin Dry Out: Uncover the turkey, then return it to the refrigerator. Refrigerate uncovered for 24 hours, or until 1 hour before cooking. This step dries the skin, which is important in order for it to crisp. The skin will turn somewhat translucent.

1 Hour Before Cooking – Let the turkey come to Room Temperature: Remove the turkey from the refrigerator and let stand at room temperature (do not brush off the brine). If you haven't removed the plastic "carrier" attached to the legs, do so now. Cook as desired.