Cut the carrots, onions and celery into large chunks. Chop 1/2 of the sage, 1/2 of the parsley and 1/2 of the thyme, leaving the rest of the bunches intact.
Preheat the oven to 375 degrees F. As you can see from my picture, setting my oven temperature is a bit of a guessing game at my house. I use a thermometer that lives inside the oven to know how hot is in there for sure. This is a good idea for anyone, since many ovens don't have the best thermostats.
With the oven pre-heating and ingredients chopped, it's time to stuff the turkey.
Start by taking one quarter of an onion, a piece of celery and a chunk of carrot and stuff them inside the body cavity. Continue stuffing some of each items inside the turkey until the turkey is full. Don't jam too much in there.
A stuffed turkey will quickly give you diminishing returns since the more you put inside, the longer the turkey will need to cook for, and the dryer it will be.
Tie the remaining bunches of parsley, sage and thyme together using a piece of butchers string and place them inside the turkey with the rest of the stuffing.
I've moved away from stuffing turkeys with an actual bread based stuffing. The increase in mass slows the cooking process down, forcing the turkey to cook for too long, and thus dry it out. The onions, carrots and celery are just really there to impart flavor to the meat and drippings, not to be eaten as your typical Thanksgiving stuffing. To learn how to make a great stuffing that's prepared entirely outside of the turkey, check out scoochmaroo's Stuffing