You open ChatGPT, explain who you are, what you do, and the tone you want. The answer comes back good. Three days later you open a fresh chat and type the same background all over again.

That loop is the quiet reason a lot of people decide AI tools are more trouble than they are worth. The fix is not a cleverer prompt, it is a ten minute setup you do once. This guide shows you how to make your own AI assistant, for free, using a tool you probably already have open, no coding required.

What it really means to make your own AI assistant

When people hear “build your own AI” they picture training a model on a mountain of data. That is not this: you are not building anything from scratch, and you are not touching Python.

You are creating a saved shortcut with a name, a set of standing instructions, and often a few files attached. Every time you open it, the assistant starts with that background already loaded, like briefing a new colleague properly once instead of reintroducing yourself every morning.

This is not the same thing as an AI agent, which goes off and completes tasks on its own. A custom assistant does not act for you, it just stops forgetting who you are. Our guide to AI agents explained simply covers that difference.

Why a saved assistant beats a very long prompt

You could paste your background at the top of every chat. Plenty of people do, but it has three problems.

• You have to remember to do it, and you will not on the day you are rushed.
• Long background eats into the space the model has to work with, a limit we explained in what is a context window. Spending that room on the same introduction every time is waste.
• Small differences creep in. You describe yourself slightly differently each time and the answers drift with you.

A saved assistant fixes all three at once. The instructions sit outside the conversation, they are identical every time, and any files you attach stay attached.

Option 1: ChatGPT Projects

OpenAI calls these Projects, described in its help pages on Projects in ChatGPT as workspaces that keep chats, files and custom instructions in one place. They are available to all free and paid subscription types globally, so you do not need to pay to try one, just be signed in.

• Click New project in the sidebar and give it a name.
• Open the three dot menu, choose Project settings, and write your instructions there. OpenAI notes these apply only inside that project and override your global custom instructions while you are in it.
• Upload your reference files. OpenAI lists the limit as five files per project on a free account, twenty five on Go and Plus, and forty on Pro, Business, Edu and Enterprise.

Projects also keep their own memory of the chats inside them, and a setting can switch a project to project only memory if you would rather it ignored everything else in your account.

Option 2: Gemini Gems

Google’s version is called a Gem. Its getting started guide for Gems describes them as customised versions of Gemini for repetitive tasks or deep expertise in new areas. The only requirements listed are a personal Google Account and being 13 or over, or the applicable age in your country. No paid plan is required.

• In the Gemini web app, click Explore Gems, then New Gem.
• Name it and write the instructions.
• Under Knowledge, add files from your device or from Google Drive.
• Click Save. Google specifically warns that trying your Gem in the preview panel does not save it, which catches a lot of people out.

Two extras help if you are stuck: a button that asks Gemini to rewrite and expand your instructions, and premade Gems (Brainstormer, Coding partner, Writing editor) you can open and copy the pattern from.

Option 3: Claude Projects

Anthropic’s help page on projects, updated in July 2026, says projects are available to all users including free accounts, and that free users can create a maximum of five of them.

A Claude project is a self contained workspace with its own chat history and knowledge base: you upload documents, set project instructions, and every chat inside starts from that base. The heavier retrieval feature for very large amounts of uploaded material is limited to paid plans, and sharing with colleagues is a Team and Enterprise feature.

If you are not sure which of the three to start with, the honest answer is whichever one you already have open. Our ChatGPT vs Gemini vs Claude comparison goes into how they differ in day to day use.

How to write instructions that actually work

This is where most custom assistants fall down: people write “be helpful and professional”, then wonder why nothing changed.

Google’s own guidance on writing Gem instructions splits the job into four parts, and the same four work just as well inside ChatGPT and Claude:

• Persona. The role it should play and how it should speak to you.
• Task. What it should actually produce.
• Context. Your background, constraints and audience, and anything it would otherwise guess wrong.
• Format. Length, structure, bullet points or prose, and what to leave out.

You do not need all four. Two or three specific ones beat a paragraph of vague adjectives every time, the same habits that make a single prompt work. Our guide on writing better AI prompts applies directly here.

A short example you can copy

Say you write lab reports as a final year student. Rather than explaining that every week, the instructions might read:

You help me write and revise undergraduate biology lab reports. Use plain, precise academic English and British spelling. Never invent citations or results. When I paste a draft, point out unclear reasoning and missing method detail first, before you comment on grammar. Do not rewrite my text unless I ask you to. Give feedback as a short numbered list.

Attach your module handbook and marking rubric as files, and every chat in that project already knows the rules you are marked against. You never type any of it again.

What to keep out of your assistant

From my own experience working with websites, online tools and cybersecurity, this is the part people skip. A file you upload is not a one off. It sits there for every future chat until you delete it, and anyone you later share the project with can usually read it too.

Keep out anything you would not want sitting in a cloud account for months: passwords and API keys, ID or passport scans, client contracts you do not have the right to share, medical records, and unpublished confidential work. OpenAI also notes that on Free, Plus and Pro accounts, project information may train its models if “Improve the model for everyone” is switched on, so check that toggle before uploading anything sensitive.

Important tip: before you attach a document, ask yourself one question. Would I be comfortable if this file were still sitting in this account in a year, readable by anyone I ever share the project with? If the answer is no, paste in only the paragraph you actually need instead of the whole file.

Our guide on using AI safely and protecting your privacy goes further on the settings worth changing before you upload anything.

Common Questions

Do I need to pay to make my own AI assistant?

No. OpenAI says Projects are available to all free and paid subscription types, Anthropic says projects are available to all users including free accounts with a limit of five, and Google’s Gems guide lists a personal Google Account and a minimum age rather than a paid plan. Paid tiers mainly raise the limits, such as how many files you can attach.

Is this the same as training my own AI model?

No. You are not changing the underlying model at all. You are saving instructions and files that get applied at the start of each chat. The model doing the work is the same one everyone else is using.

How many assistants should I make?

Fewer than you think. Two or three matching things you genuinely do every week will get used, twelve will not. Start with one and only add another when you catch yourself typing the same background again.

Will my assistant remember what I told it in an earlier chat?

That depends on the tool and its settings. ChatGPT projects keep their own memory of chats inside them, and you can set a project to ignore everything outside it. Treat the standing instructions and uploaded files as the reliable part, and anything mentioned in passing as the part that may not carry over.

Can I share my assistant with someone else?

Sometimes. OpenAI allows project sharing across its plans, with the number of collaborators depending on the plan. Anthropic limits project sharing to Team and Enterprise accounts. Before you share anything, remember that everyone you invite can usually see the files you uploaded.

Final takeaway

Making your own AI assistant is not a technical project. It is ten minutes of writing down what you would tell a new colleague on their first day, saved somewhere the tool reads it every time. Pick the chat tool you already use, create one assistant for the task you repeat most, and edit the instructions properly after a week of real use. That one setup will save you more time than any prompt trick you will ever read.