Prep the pot.
A lot of people use too much oil. Three gallons in the right pot is plenty to fry a whole turkey. A good way to determine if your pot is the right size is the displacement method: Put your turkey into the pot while it's still in the package, fill it up with water to cover, and then remove the turkey. Whatever the water level is at is where you want your oil to be. Don't skimp on the pot.