Which way should an internal star lock washer go?
The jagged side should be to the bolt nut, not the washer. You're trying to prevent the bolt nut from turning, thus unscrewing. The jagged side will, to a small degree, bite into the metal of the bolt to increase the holding power. (The majority of the holding power is from just the compression of the lock washer.) Turned the other way will work, just not quite as well. (you don't really care about the washer turning.)

Edit: correct my stupid mistake!