No need to marinated in anything as they have enough fat. S&P is the basic type rub down as mentioned above; I like to add garlic, onion, paprika, and a chili you like if you want to add a little flavor to accentuate the smoke and beef. Main thing is keep it simple and let the meat and smoke do the work. Cook it until it is probe tender or if your not sure 200 in the point or 195 in the flat, then let rest for a couple hours well wrapped in a cooler or your oven.