Keep sentences, paragraphs and stories short. Just as with your newsletter as a whole, each story, paragraph and even sentence should have a purpose. These goals will help you keep readers in mind so your words don't stray from the effect you want. The answer is your lead paragraph. Look for the personal angle to any story.
People are interested in what other people are doing.
Don't overuse description, humour, value judgment, adjectives and nouns. Use strong verbs, it helps make other words work. They link directly to the reader's senses - touch, sight, smell, sound and taste. Use simple words, action, direct questions and contractions. Who, What, When, Where, Why - and How.