If you are doing it in the oven, here's the general guidelines:

Do not rinse first.  It serves no purpose and you'll just spread germs around your kitchen.

Don't bother putting it breast side down.  It doesn't actually keep the meat any more moist.

Butter gives more moisture than oil, more flavor, and makes the skin less likely … Read more

I like turkey smoked on a smoker! You can also cook it breast side down, I hear it stays more moist that way.