If you are content on marinades, just use straight up Italian dressing. The vinegar breaks down the muscle tissue making for a more tender steak and the adding seasoning penetrates deep. If you're going to use this method...marinade it for at least 2 days in the fridge.
NEVER put salt on a steak during pre-cook or during the cooking process. Salt tends to force out moisture which will leave you with a dried up beef jerky steak. If you're going to use salt, add it after it cooks to taste.
