All resources Prompts
A free guide by ZAK
ChatGPT Custom Instructions That Stick
If you fix the same AI mistake twice, it should become a rule. Here is how to turn corrections into ChatGPT custom instructions, and how to ask for one fix without AI rewriting everything.
Most frustration with AI comes from repeating yourself. Shorter please. No jargon. Stop opening emails with hope you are well.
Every one of those corrections is a rule waiting to be saved. Save it once and the mistake mostly stops.
Step 1
Keep a Correction Log for a Week
Each time you correct AI, copy the correction into a note. By Friday you will have your rules.
Step 2
Turn Corrections Into Rules
Paste your log into this prompt. It groups and rewrites them as clear instructions.
Here are corrections I gave AI this week: [PASTE LOG] Group them by theme. Rewrite each group as one short, clear rule AI can follow. Remove duplicates. Output a numbered list under 200 words that I can paste into custom instructions.
Step 3
Save Them Where They Load Every Time
In ChatGPT, look under Personalization in Settings for Custom instructions. In a ChatGPT or Claude Project, paste them into the project instructions so they apply to that work only.
MY RULES FOR AI 1. Lead with the answer. Reasons after. 2. Short paragraphs, plain words, no jargon. 3. Never invent numbers, names, quotes or sources. 4. When editing, change only what I ask. Show changes in a list. 5. No filler openings or sign offs in emails. 6. Canadian spelling. 7. If my request is unclear, ask one question before you start. 8. [ADD YOUR OWN]
Step 4
Ask for One Fix at a Time
When you only want one change, say so plainly and ask AI to show what it changed.
Change only this: [THE ONE THING]. Keep every other word exactly the same. After the revised text, list each change you made in one line.
Step 5
Review the Rules Monthly
Delete rules AI now follows anyway. Add new ones from your log. Keep the file short. Long ones get ignored.
Questions About ChatGPT custom instructions
What are ChatGPT custom instructions?
Saved guidance ChatGPT applies to every new chat, such as your role, preferred format and rules to follow.
Where do I find custom instructions in ChatGPT?
In Settings, under Personalization. Names may change, so search settings for custom instructions.
What should I put in custom instructions?
Your role, how you want answers formatted and the rules that fix mistakes you keep correcting.
How do I stop ChatGPT rewriting my whole document?
Ask it to change only one thing, keep every other word the same and list the changes it made.
Next step
Put This Guide to Work
Bring your house style and your common mistakes and we can write instructions your team can share.