I remember having to stand on a crowded open deck, and watch a crewmember go through the motions of putting on a life vest. He wouldn't begin his demonstration until all the passengers assigned to our section were present and accounted for. In later times, we did the muster call in the theater or a restaurant. This was somewhat better, because we could sit. Yeah, Once or twice to watch the video at home should be enough.
Life vests used to be stored in the cabin closet. We didn't find any there on our last cruise.