The single biggest improvement.
WHAT VAGUE PROMPTS PRODUCE
Generic output that could apply to anyone.
VAGUE
"Write about customer service."
SPECIFIC
"Write 400 words for a small Nigerian retailer on handling complaints about late delivery. Practical, with what to say. For an owner with no formal training."
WHAT CHANGED
The audience, the topic, the length, the purpose, the register.
WHAT TO SPECIFY
Who reads it What they should do afterwards How long What to include What to avoid
THE LENGTH INSTRUCTION
State it. Without it you get whatever length the model defaults to.
"Around 300 words" or "three short paragraphs" both work.
THE AVOID LIST
Genuinely effective. Naming phrases you dislike removes them.
"Do not use: leverage, delve, landscape, unlock, game-changer."
WHAT NOT TO DO
Assume the model will infer your situation. It cannot.
THE TEST
Could someone else follow this prompt and produce what you wanted?