First off, if you're thinking heritage turkey, read this post.
Second, if you haven't brined before, I recommend brining a chicken before you test your skills on the Thanksgiving guests.
Third, consider whether you really need to add the step. Not only is it one more item to add to your "to do" list, but you'll have one more day of negotiating around the bird, in its brine, in the refrigerator.
I've tried it once, and failed. Yes, it happens. Blame it on unclear instructions and a harried cook. Add those two together and it equals disaster. Kosher birds are already salted so you definitely don't want to brine if you've chosen Kosher.
Suppose you do wish to brine - here are some key steps and ingredients: