I love to host Thanksgiving dinner. Most years you'll find a mixture of family, friends, and stragglers—always an eclectic group. Over the years, I've refined my turkey roasting technique to the point that I don't even think too much about it - here are a few tips to help you produce the perfect roast turkey:

• Buy the best turkey you can afford. I always order from my butcher a free range, hormone-free hen- they cost more, but are well worth the extra flavor punch they deliver.
   

• Note that it takes 24 hours per 5 pounds of turkey to defrost a frozen bird in the average refrigerator. If you're going to roast a 15 pound bird Thursday morning you need to have it out of the freezer by Monday morning at the very latest. If you have to buy frozen, look for one that has been injected with all-natural ingredients, no saline solutions.
   

• Invest in a good roasting pan—avoid the cheap aluminum disposable pans at all costs. They steam rather than brown the bird, are dangerous because they may buckle when you pull them out of the oven, plus you can't make gravy in them. You'll use a good roasting pan for many things once you have one. It's well worth the investment.
   
• Before you put the bird in the oven, completely submerge it in a pot full of cold water for 10 minutes. Drain and repeat at least twice, refilling the pot with cold water each time. 
   
• Drain the bird thoroughly.
   
• If you're planning to inject a marinade, seasonings, or secret family concoction into your turkey, now is the time to do it. We recommend the 6" Signature Fat Boy from Cajun Injector for your big bird. 
   
• Proceed with your favorite roasting process.
   

Assuming a 325ºF oven, estimate the following roasting times for an unstuffed turkey:

• 8 - 12 pounds: 3 hours or a bit less
• 12 - 14 pounds: 3:45 hours or a bit less
• 14 - 18 pounds: 4:25 hours or a bit less
• 18 - 20 pounds: 4:30 hours or a bit less
• 20 - 25 pounds: 5 hours or a bit less
   

You should have an instant-read thermometer. You want the internal temperature of the bird to get to 180ºF at the thickest part of the thigh for a perfectly-done bird.

For a stuffed bird, add 15 minutes roasting time, and always remove the stuffing to a separate container as soon as you remove the stuffed bird from the oven.
 

Some more important turkey handling, prep and cooking tips from the USDA
Turkey Basics - Safe Cooking | Turkey Basics - Safe Thawing | Turkey Basics - Safe Stuffing | Turkey Basics - Storing Leftover Turkey