Some folks try to make this way more complicated than it is. If you clean and dry/cure the fan properly, displaying it is simply a matter of running a screw, nail, or pin through the base or even just a center feather quill (as Southerngobbler outlined). You can dress it up however you want beyond that.
The most important part of the entire process is cleaning the fan base well and then putting a preservative on it (using borax is the simplest way). Here are the steps: 1) kill a gobbler (may be the toughest part for some folks
) 2) cut the fan off leaving the base of the fan intact 3) clean as much of the meat and fat off of the base as you can,...but still leaving the fan base intact 4) spread the fan and pin it down on something (cardboard is great) in the shape you want it 5) let it dry for a couple of weeks, adjusting the feathers as needed while drying to make sure they are all symmetrical (add pins as needed to hold feathers in shape wanted) 6) remove from cardboard (once it is dry and will hold its shape) and add more borax to base 7) screw/nail/pin to wall.
The entire process, from dead bird to fan-on-wall should take no more than a couple of hours (total time involved other than drying) to accomplish.
