also, resist the tempation to open your oven and "check on the turkey." don't worry, it's cooking in there. only open the oven to take the foil off and then check the temperature.
opening the oven releases heat and cools down the oven thus increasing cooking time.
in my opinion, birds that are wrapped and left alone to cook always turn out better than birds that are basted every 15 minutes mostly because with all the heat escaping and the longer cooking time, the bird has more time to dry out.
by covering the roasting pan with foil (as your recipe states) or using one of those plastic roasting bags and sealing it all up, the broth or water you add bastes the turkey with steam throughout most of the cooking process.
one more tip not to forget, LET IT REST!!! after it is cooked and out of the oven and BEFORE you carve it, loosely tent it with foil and WAIT at least 20 minutes. this is a good time to deglaze the pan and make gravy out of the drippings. cooking brings the turkey's natural juices to the surface of the meat. allowing it to rest lets the juices redistribute throughout the whole bird.