With my little one's I haven't had stuff planned out re: safety but it just happens...like crossing the street - looking for cars, or when we're in a parking lot the rule is: 1 hand has to be on the red circle (rear lights) of my car at all times, no running etc.
Oh yeah we also do the hand holding...we don't move unless we're a link! But like PP said my group are all 3 & under so I think it's enough for now :P