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Brainstorm sale subject lines that fit on a phone screen
Practice: Setting limits and rules. About 5 minutes.
About this exercise
You're writing subject lines for Larkspur Home's linen sale email, and phones cut off anything over 40 characters. You need exactly 5 numbered subject lines, each under 40 characters (about 6 words), with no emojis and no words in ALL CAPS. Use the final offer details, not the ones from the first draft of the brief. Reply with only the plain-text list, no intro or notes. Write a prompt that gets that list.
Common mistakes when you ask AI for this
- Asking for "some subject lines". The AI gives 10 to 15 options, often grouped under bold headings like "Urgency" and "Playful". Try: Set the count: "Exactly 5 numbered subject lines, plain text."
- Not giving a length limit. AI writes full-sentence subject lines that get cut off on a phone halfway through the offer. Try: Add: "Each subject line 3 to 6 words, under 40 characters."
- Using the first draft's offer. The brief starts with 30% off and free shipping, and AI grabs the biggest numbers it sees. Try: Add: "Use Ines's Nov 3 update: 25% off, no free shipping."
- Letting it shout. Sale emails pull the AI toward emojis, CAPS and an intro like "Here are some options". Try: Add: "No emojis, no ALL CAPS words. Output only the list."
What a strong prompt includes
- Says how many
- Sets a length limit
- Uses the updated offer
- Rules out emojis and caps
- Asks for only the list
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