According to Martha Stewart, the way to season your turkey under the skin is: "Loosen skin: Working from the neck end, slide fingers under skin until you reach the end of the breast, being careful not to tear the skin" . Thanks, Martha. We'll get right on that!
Shave some of your fresh truffles and lay them out on some butter. Once the skin of your bird is loosened, use a long skewer or the end of a wooden spoon to push in your shaved truffle slices. Use that now flavored butter to rub on the skin of the bird for extra flavor.
The truffle flavor will permeate the entire turkey! Bon appetite!