Say who, what and how
A weak prompt gets a weak answer. Tell it the role ('you're a friendly plumber'), the task ('reply to this enquiry'), and the format ('short, warm, 3 sentences').
Show an example
Paste an example of the tone or output you want. AI copies patterns brilliantly — one good example beats a paragraph of instructions.
Iterate, don't restart
Treat it like a conversation: 'shorter', 'more formal', 'add a call to book'. You'll get to a great result in two or three nudges.
Refine with small nudges — two or three usually get you there — rather than starting over.