What you’ll make
Set one preference you can see working in a fresh ChatGPT chat.
Worked example
A booking app update and a grocery checklist
A solo developer wants ChatGPT to lead with the answer and ask about missing facts. Their Release Notes Project has one approved note and a glossary for a small booking app.
A new Project chat turns a test ticket into an update about the “Reschedule” button. An ordinary chat turns three ingredients into a grocery list. If the ticket leaves out the version, the Project asks for it before using a release label.
Before you start
- Choose a task you do often and an unrelated task for a second test. Use invented details or an example you are comfortable adding to your workspace.
- Open the correct account or workspace and note the tools it offers. Base any plan decision on a specific missing capability or a limit you have actually encountered.
Choose one change you’d notice
Pick a preference you want in most chats. Describe what a reply would do differently, such as putting the action up front. Keep product names and rules for a specific job in that job’s chat or Project.
I want short lists that I can scan. I can check that with a three-item grocery request.
I’ll know it worked if I see the list right away and the three items are easy to pick out.
Write and add the preference
Copy the prompt into ChatGPT. Read the sentence it gives you, then open Settings and look for Personalization and Custom Instructions. Add the sentence alongside any instructions you want to keep and save the change.
I say I want the action first and short lists when there are several items.
I might get “Start with the action I can take, then use a short list when there are several items.” That’s the sentence I’d add to Custom Instructions.
Write one ChatGPT preference I can check
Write one sentence I can paste into ChatGPT’s Custom Instructions. Use the details I provide in this chat or in my attachments. Use a clear instruction that would help with my everyday chats. Base it on the behavior I described, without turning my test topic into a rule. If the preference is too vague to observe in a reply, ask one question about what I want to see. Once you have it, return only the instruction sentence.
Give it one simple request
Start an ordinary fresh chat and send the test request from step 1. Look for the behavior you wrote down. If the reply misses it, make the sentence more specific and run the same request again.
Keep the wording that worked
Save the exact preference and test request together. That gives you a simple way to check the setting again after future edits.
- The instruction applies to everyday chats.
- The test started in a fresh ordinary chat.
- The reply shows the specific behavior you wanted.
Optional: Try a second request
Give ChatGPT a different task in a fresh chat and see whether the preference still helps. Keep project-specific wording with that project and save only preferences you want across chats.
Write my everyday instructions and my project brief
Paste this with a repeat task and a sample answer you’d actually use.
I use ChatGPT for [regular work]. Here’s a normal request and an answer I’d actually use: [short example]. Here’s something it keeps doing that I’d like it to stop: [example]. My preferences across chats are [tone, structure, terminology, or how to handle unknowns]. Draft two blocks I can paste into settings: short Custom Instructions that make sense in any chat, and a Project brief for [repeat job]. In the Project brief, name the inputs, the result I want, and the file or product fact to check before making a claim. Keep customer details and temporary facts out of the account-wide instructions. If you only have one sample, mark what you’re assuming. For each block, give me one example sentence I’d recognize as evidence that the instruction worked. Show me exactly what to paste and keep your explanation outside the two blocks.
Try a normal task and one outside the project
Run these in fresh chats to see whether your preferences and project details land in the right place.
Here are my draft account instructions and Project brief: [paste both]. Write two short test requests I can run in fresh chats. One belongs in [Project name] and should use [specific reference or wording]. The other is an unrelated everyday request and should still follow my broad preferences. Give me a small pass/fail table for each. Include one observable style check, whether it used the correct source or terminology, and whether it made up a missing fact. For the project test, remove one detail from the inputs and tell me what it should ask before answering. Use fictional details so I can share the results back safely.
Troubleshooting
My request still sounds too formal. Where should I look?
Check the conversation instructions, the project instructions, and relevant memories for a more specific style rule. Test a short request after editing just one place.
What if the project tool I need is unavailable?
Keep a local brief and paste the necessary excerpt into a new chat for your test. Compare the tools and limits shown for your workspace if the manual step becomes a recurring bottleneck.