The Ultimate Codex Tutorial: How To Use Codex For Beginners 2026

Codex is OpenAI's coding agent for turning plain-language instructions into real work: building pages, editing files, testing interfaces, creating documents, connecting to tools, and running repeatable tasks in the background. This beginner guide follows the workflow shown in Charlie Chang's video and turns it into a practical step-by-step guide you can follow inside the Codex app.

The example project is simple on purpose: create an AI newsletter landing page, improve it, generate a newsletter workflow, build a marketing plan, and create a short promo video. By the end, you will understand the basic Codex loop: describe the outcome, give Codex the right context and permissions, review the plan, let it work, then inspect and improve the result.

1. Download and Open Codex

Start by going to the Codex download page from your browser. In the video, the flow begins at chat.openai.com/codex, where the macOS app can be downloaded. After downloading, drag the Codex app into your Applications folder, open it, and sign in with your ChatGPT account.

During onboarding, Codex may ask what kind of work you do, such as engineering, product, or marketing. Pick the closest option. If you already use ChatGPT, Codex may also offer to bring in projects or connected tools from your account.

Beginner tip: when Codex asks for local access, think about the kind of work you want it to do. If you want it to edit files, inspect folders, or work across a project on your computer, it needs permission to see the relevant files. Start with limited access if you are experimenting, then expand permissions only when the task requires it.

2. Understand the Codex Workspace

The main Codex screen is where most work starts. You can think of it like a ChatGPT conversation with more tools attached.

The sidebar helps you move between new threads, older chats, projects, plugins, automations, and settings. A thread is a conversation where you ask Codex to do something. A project is a more durable workspace connected to a folder or body of work, useful when Codex needs ongoing context.

Before sending a task, check three things:

1. Choose the right project, or leave it as a standalone thread.
2. Set the permission level that fits the job.
3. Pick the model or reasoning level that matches the complexity of the work.

For quick writing or small edits, a lower reasoning level may be enough. For multi-step work such as building an app, reviewing a UI, or creating a plan, use a stronger reasoning setting so Codex has more room to think through the task.

3. Set Up Plugins and Connectors

Connectors and plugins are what let Codex work beyond a plain chat box. In the video, the useful setup includes tools such as GitHub, browser use, computer use, Google Drive, and Hyperframes by HeyGen.

Use connectors when you want Codex to interact with real tools or data. For example:

• GitHub helps Codex work with repositories.
• Browser use helps Codex open and test web pages.
• Computer use helps Codex interact with desktop UI when needed.
• Google Drive helps Codex create or edit Docs, Sheets, and Slides.
• Hyperframes can help Codex create a motion graphic or promo video.

You do not need every connector on day one. Add the ones that match your workflow, authorize them carefully, and confirm that Codex only has access to the accounts and files you actually want it to use.

4. Create Your First Landing Page

The first real project in the video is an AI newsletter landing page. The prompt gives Codex a clear outcome, a business context, and the page elements it should include.

Use a prompt like this:

Create a modern, clean, beginner-friendly landing page for an AI newsletter business. Call the newsletter "Omri's AI Newsletter." Use a green color scheme. Include a headline, subheadline, email sign-up box, feature section, and a clear call-to-action button. Start in plan mode first so I can review the implementation plan before you build it.

This is a good beginner prompt because it gives Codex enough direction without over-specifying every pixel. Codex can propose a plan, explain what it will build, and then you can approve the implementation.

When Codex gives you a plan, read it before clicking yes. Check whether it understood the product, audience, page sections, styling, and success criteria. If the plan is vague, ask Codex to make it more specific before it starts editing.

5. Let Codex Build, Then Inspect the Result

After you approve the plan, Codex starts building. Depending on the task, it may create files, generate assets, run commands, open a browser, take screenshots, and test whether the result looks correct.

This is where Codex becomes more than a text assistant. A good workflow is:

1. Ask for the outcome.
2. Review the plan.
3. Let Codex implement.
4. Watch for test results or screenshots.
5. Ask for refinements.

For a landing page, do not judge only the first version. Check whether the headline is strong, the signup form is visible, the layout works on mobile, and the call to action is clear.

6. Create an Automation

Automations let Codex repeat a task on a schedule. In the video, the example is a daily newsletter draft: Codex looks up recent AI news, writes a short newsletter, and prepares it for the audience.

Use a prompt like this:

Every day at 9:00 AM, find the latest AI news and create a short email newsletter draft for my AI newsletter audience. Keep it beginner-friendly, practical, and easy to scan. Include a subject line, intro, three short news items, and one actionable prompt readers can try.

Once the automation is created, use "Run now" to test it before trusting the schedule. This first run is important because it shows whether Codex understood the format, tone, and level of detail you want.

Beginner tip: a good automation is specific and repeatable. Avoid prompts like "send me useful updates." Instead, define the source, frequency, output format, audience, and review step.

7. Ask Codex to Improve Its Own Work

The first version of a page is rarely the best version. In the video, the landing page works, but the design and copy can be improved. The next move is to ask Codex to review its own work like a product designer, copywriter, and QA tester.

Use a prompt like this:

Review the landing page you created. Look at the UI, copy, layout, mobile experience, and conversion flow. List the main things that should be improved, then make the improvements. Keep the page beginner-friendly and aligned with the green newsletter brand.

This is one of the most useful Codex habits: do not just ask it to create. Ask it to critique, verify, and iterate. Codex can often spot weak copy, unclear hierarchy, missing states, or layout issues if you explicitly ask it to inspect the work.

8. Create a Marketing Plan in Google Drive

Once the landing page exists, the next step is strategy. In the video, Codex uses the Google Drive connector to create a full marketing plan as a Google Doc.

Use a prompt like this:

Create a new Google Doc with a full marketing plan for Omri's AI Newsletter. Include an executive summary, target audience, positioning, acquisition channels, weekly content strategy, launch plan, metrics, and next steps. Make it practical for a beginner-friendly AI newsletter.

This shows how Codex can move from building a product asset to supporting the business around it. The point is not just that Codex can write a document. The point is that it can use the context from your project, create a structured plan, and place it where your team already works.

Review the document before using it. Ask Codex to make it shorter, more specific, more aggressive, more budget-conscious, or more founder-friendly depending on your real situation.

9. Create a Promo Video with Hyperframes

The final creative step is a short marketing video. In the video, Codex uses the Hyperframes by HeyGen connector to create a roughly 30-second promo video for the AI newsletter.

Use a prompt like this:

Use HeyGen Hyperframes to create a roughly 30-second promo video for Omri's AI Newsletter. The video should tease practical updates about Codex and GPT-5.5, and encourage viewers to sign up for the newsletter. Use the same green visual style as the landing page. Create a five-step showcase of what readers will learn. Do not let text or graphics overlap. No voiceover for this version.

Be specific about duration, audience, visual style, voiceover, and what should not happen. For video generation, negative constraints matter. If you do not want overlapping text, tiny captions, or too much motion, say that upfront.

10. Review the Final Asset

After Codex creates the video, review it the same way you would review work from a teammate. Check the text, pacing, brand consistency, visual spacing, and whether the call to action is obvious.

You can then ask Codex to:

• add music,
• add a voiceover,
• shorten the script,
• create a vertical version for social media,
• export alternate copy,
• or generate a second version with a different tone.

The key lesson is that Codex is strongest when you use it iteratively. Treat each output as a draft you can improve, not as a one-shot final.

Beginner Workflow to Remember

For almost any Codex task, use this pattern:

1. Start a thread or project.
2. Give Codex a clear goal.
3. Add context, audience, files, and constraints.
4. Ask for a plan before implementation.
5. Approve the plan.
6. Let Codex work.
7. Review screenshots, files, test output, or generated documents.
8. Ask for improvements.
9. Save repeatable tasks as automations.

Here is a reusable beginner prompt template:

I want to create [outcome]. The audience is [audience]. The style should be [style]. The result must include [required elements]. Use [tools/connectors] if needed. Start by giving me a short plan. Wait for approval before implementing. After implementation, test or review the result and tell me what you changed.

Best Practices for New Codex Users

Start with one concrete task. Do not begin by asking Codex to "build my whole business." Ask it to create one landing page, one document, one test, one automation, or one improvement pass.

Use projects when context matters. If Codex needs to remember files, brand direction, product goals, or previous work, put the task in a project rather than a random standalone thread.

Give permissions deliberately. More access can make Codex more capable, but it also means Codex can touch more of your workspace. Match permissions to the job.

Ask for plans. Plan mode is especially useful for beginners because it lets you catch misunderstandings before Codex edits files or creates assets.

Review everything. Codex can build quickly, but you are still responsible for the final judgment. Check facts, copy, links, design, and any external files it creates.

Turn repeated work into automations. Once you have a prompt that consistently produces the right result, schedule it.

Final Takeaway

The beginner-friendly way to use Codex is not to memorize every feature. It is to learn the working rhythm: connect the right tools, describe the outcome clearly, let Codex plan, approve the work, review the result, and iterate.

In the video workflow, Codex goes from a blank workspace to a landing page, a newsletter automation, an improved design, a Google Doc marketing plan, and a promo video. That is the real lesson: Codex can help across the full lifecycle of a project, from idea to execution to marketing, as long as you give it clear context and keep reviewing the work as it develops.