This method for roasting differs from others because it is done on a high heat. I do not recommend cooking more than a 16-pound (7-kilogram) turkey this way. For larger birds, start at 400 F for the first hour and then turn down the oven to 350 F for the remainder of the time. The turkey is cooked when an instant-read thermometer inserted into the thickest part of the turkey reads 165 F.
To truss the turkey, the perfect thing is the Food Loop Lace: an ingenious silicone needle and thread you can use to sew up chicken and just about anything else. Just wash and reuse. Available at kitchen stores.