Thaw turkey. 24 hours for every 5 pounds of turkey. If your turkey is 20 pounds, you'll need to thaw starting Saturday for 4 days.
Add all ingredients to a large pot.
Bring to a boil and cook until salt and brown sugar are dissolved about 20 minutes.
Let cool to room temperature or add ice to chill quickly or place in the fridge until chilled.
Open the thawed turkey up and remove, the neck and gravy packet and giblets.
Rinse off turkey
Once the brine is chilled place turkey in the brine, breast side down, and place in the fridge (ensure turkey is completely covered and cavity filled.)
If brine is not enough, then cook up 4 Tablespoons of salt for every 4 cups of water. until the turkey is covered. Remember to not add hot water to the turkey, but only room temperature or chilled.
If your turkey tries to float in the water, put a plate on top of it to weigh it down.
Place turkey & brine in the fridge for 12 - 24 hours. See notes for alternative brining storage options.
After brining, drain the turkey, rinse, pat dry, and cook. If possible, let the turkey rest for 1 - 2 hours before cooking, optional but recommended.