To maximize its shelf life, raw steak should be kept in its original packaging until it's ready to be used. If the original packaging has been opened or if the steak is leftover from a meal, wrap it tightly in plastic wrap or aluminum foil, or place it in an airtight container. This will protect it from exposure to air and bacteria, which can hasten spoilage. Remember to store it in the coldest part of your fridge, typically the lower back section.