You are a LinkedIn expert and copywriter. Write a detailed, 1800-word post on writing recommendations. The post must cover: 1) The specific achievement formula, 2) The character and skills formula, 3) The working relationship formula, 4) The results formula, 5) The personal story formula, 6) Examples for each formula, 7) Getting recommendations in return, 8) Formatting and length, 9) Authenticity and sincerity, 10) Timing and follow-up.