General announcement of subject, perhaps a question or quick observation.
Something from current events or well-known history or mainstream philosophy to tweak interest.
Personal observations, how it relates to you the writer.
Something touching on Grandma Slump's life, perhaps a recent jaunt in Heaven.
Bringing it back to Earth, with humorous insights and something quite amusing to the general reader.
Saying "Be that as it may," or "Only time will tell," and drawing a moral. Wrapping it up too neatly betrays the form, so drift out, keep it mildly ambiguous at the end.