Custom Instructions For Better ChatGPT Results

Most business users think that productivity with ChatGPT simply means better prompting.

But there’s a cheat code: tell ChatGPT how to behave before you even start.

That’s what Custom Instructions are for. In just two fields, you can define what ChatGPT should know about you—and how it should speak to you.

It’s how you set default preferences for an AI colleague.

Shape how ChatGPT thinks, speaks, and helps—without writing a single prompt.

Save time with custom instructions so ChatGPT sounds like you, thinks like you, and works how you do.

When you hire a new employee, there’s usually a set of rules and guidelines for how they should interact. Policies on giving refunds, or how you address customers. With ChatGPT you can and should do the same thing.

The Custom Instructions feature allows you pre-load ChatGPT with key context about your work, goals, and preferred tone, it stops acting like a generic chatbot and starts performing like an informed digital teammate.

Pair this with memory and you have a digital assistant not a glorified search engine.

Custom Instructions reduce friction and help ensure better consistency. They somewhat eliminate the need to repeat your background, tone, or goals every session. I say "somewhat" because AI models are probabilistic, not deterministic. So sometimes even with the best guidance your ChatGPT session may go off the script.

But by and large these custom instructions ensure consistent communication, which is vital when you’re working across multiple projects, teams, or functions.

More importantly, they let you set a default personality and intent for ChatGPT. Whether you need a formal analyst, a casual writing partner, or a hyper-concise strategist, you can define that behavior up front.

You can set up Custom Instructions in less than a minute:

You’ll see these fields:

Changes take effect immediately and apply across all new chats—unless you override them with a specific prompt.

You could write your custom instructions from scratch but I find that you can get a great start by using ChatGPT. By feeding ChatGPT your LinkedIn profile, resume, and a few writing samples, you can have it generate a tailored first draft of your custom instructions in minutes. Then open them in Canvas to tweak them. You’ll define what you do, how ChatGPT should respond, and anything else that improves your experience. It’s a fast, effective way to make every session more productive—especially if you’re using ChatGPT for business writing, technical tasks, or strategic planning.

Upload or reference:

These inputs provide tone, domain, and target audience signals.

Use this prompt to start the initial draft of your custom instructions.

Here’s an example of my profile. I actually update them quite often.

I’m an AI consultant, author, and founder of Peripety Labs. I advise companies on how to move from AI experimentation to operational adoption. I write The Artificially Intelligent Enterprise, a weekly newsletter for business professionals focused on real-world AI applications. My background includes over 30 years in enterprise software, open source, and cloud computing. I also train executives and teams through the AIOS S.M.A.R.T. framework to integrate AI into business workflows.

Responses should be structured, clear, and concise. Avoid filler language, hype, or buzzwords. Use segmented formatting for complex tasks. Emulate the tone and precision of publications like the Wall Street Journal or Ars Technica. Avoid emojis, fluff, or AI-sounding phrasing. Use real-world examples, cite sources when appropriate, and suggest next steps or formats when producing deliverables.

My audience includes mid-level to senior executives who value strategic insight and operational clarity. I often publish under time constraints and rely on ChatGPT to accelerate writing, prompt design, and technical synthesis. I prefer direct feedback loops, structured iterations, and detailed comparisons. I work across corporate, developer, and public-sector audiences, so versatility in tone and framing is important.

Go to the Blue Diamond Menu → Customize ChatGPT, then paste your completed answers into:

Custom Instructions allow you to fine-tune how ChatGPT interacts with you, tailoring its responses to match your needs, tone, and goals. Let’s explore the benefits of using Custom Instructions, practical examples, and how to get the most out of this feature to make ChatGPT function how you want with some well thought out directions.

Executive Assistant Output

Industry-Tailored Support

Founder Messaging Prep

Suppose you’re managing client follow-ups after product demos.

Think of Custom Instructions as macro templates for how ChatGPT should behave.

By writing reusable patterns into the instruction fields, you can:

For recurring tasks, try something like this:

Now you’ve created a macro—no scripts needed.

Pro tip: Update instruction sets weekly as your focus shifts from strategy to delivery, or from writing to analysis. Or when you change roles.

Don’t expect perfection on the first try. Treat Custom Instructions as an ongoing set of directives just like you would as you would an employee:

If it starts feeling too generic, the fix is likely in your instructions—not just your prompts.

Custom Instructions can give you leverage. One minute of setup can improve every response you get, from daily memos to executive presentations without repeating yourself in every prompt.

Whether you’re in strategy, sales, operations, or finance—Custom Instructions can help you in your role.

Custom Instructions is more than a settings tweak—it’s the beginning of how you will eventually train any AI tool, whether that’s an AI agent or other AI tool. Instead of thinking “how do I prompt ChatGPT better?”, start thinking “how do I brief my assistant once so it just gets it?”

No overhead. No code. Just smarter output from the start.

I appreciate your support.