Context, task, format
Say who you are and who it's for, what you want, and the shape of the answer. 'I run a dog grooming shop. Write a friendly 3-sentence reminder text for tomorrow's appointment with the time and our cancellation policy.'
Give an example
Paste a message you liked and say 'match this tone'. Examples steer style better than adjectives.
Iterate
Treat the first answer as a draft: 'shorter', 'less formal', 'add a line about parking'. Two or three rounds usually beats one long request.
Do this today
Rewrite one real task as a context + task + format request and compare the result with a one-line request.