How to build a website or app with AI: step-by-step guide

You have an idea for a site, an app, or an online tool, and you do not want to become a developer. This guide shows how to move forward simply on Index10: from the first idea to a link you can share.

Website or application?

In practice:

• Website: read, discover, contact, sometimes book or request a quote.
• Application: sign in, come back, find your info, repeat actions.

Many projects start as a site, then become an app. That is normal. See also What is SaaS?.

Keep the first version simple

The trap is wanting everything on day one. Pick one useful thing people should be able to do:

• get in touch
• request a quote
• book a slot
• create an account and save a first piece of info

Everything else can wait. That is the spirit of an MVP.

Start in the chat

You do not need a perfect document. Open the editor and describe your idea in plain words. The AI can help you clarify before it builds.

Example:

Here is my rough idea: a site for an independent florist in Lyon, for individuals ordering bouquets. Useful pages: home, arrangements, indicative pricing, contact. No online shop for now. Help me clarify a simple first version. Ask me questions if something is missing. Do not build until I validate.

Then, when the plan feels right, ask it to build. Another creation message example:

Create a site for an independent florist. Audience: individuals ordering bouquets. Pages: home, arrangements, indicative pricing, contact. Warm, clear tone. No online shop for now. Goal: get requests via form.

How to phrase it better: What is a prompt?.

Look at the preview, then adjust

As soon as there is something to see, open the preview. Click around like a visitor, try the important path (for example: arrive → understand → contact), and check it on a phone too.

Then change one thing at a time. Example:

I clicked “Send” on the contact form. I expected a confirmation message. I saw a blank page. Fix only that.

More pace: 10 tips to build faster with AI.

If you are going in circles

Summarize what already works, then ask for one fix. Or: “propose 2 ways to fix this, then apply the simplest.”

Index10 Cloud: only if you need it

If people must sign in, or you need to keep info / files, enable Index10 Cloud (Cloud tab, or ask the AI). It is not required for a simple presentation site.

Later, if you connect online payments or automatic emails, you may be asked for a secret code. Never paste it in the chat: store it in the Cloud tab, under Secrets (a vault made for that). Details: Index10 Cloud.

Publish, then show a few people

When the important path works, publish to get a link to share.

Send that link to a small circle (clients, colleagues, relevant friends), note what blocks them, fix it. Only then widen. A custom domain is available from the Pro plan.

If people sign in, also test with a second account: each person should only see their own info. More detail: Are AI-built websites and apps secure?.

After that

Watch what people actually do, then add one feature at a time. That is how a site becomes an app, without rebuilding everything.

For the working style behind this: What is vibe coding?. Then the simplest next step: open Index10 and start with a deliberately clear idea.