Turkeys have otherworldly eyesight, so full camouflage—including a face mask—is critical. A gobbler knows his territory like you know your living room, and anything that looks the least bit out of place is sure to attract his attention.
Getting yourself comfortable with your back against a tree is equally important. With no shortage of turkey seats on the market, I can’t say that one is necessarily better than the other—just choose a model that’s comfortable for you. The more relaxed you are, the less likely you are to fidget at precisely the wrong time.
Also make sure that your calls, binos, water bottle and anything else you might want, including your shotgun, can be accessed with absolutely minimal movement—one false move when a tom is within eyesight can mean game over. Murphy’s Law is never far away when turkey hunting.