n8n for beginners: your first AI marketing automation in 30 minutes

What we are building

A workflow that takes a blog post URL, summarizes it into 3 social media captions (LinkedIn, Twitter, Instagram), and saves them to a Google Sheet. Fully automated. Trigger it with one click.

Step 1: Set up n8n (5 minutes)

• Go to n8n.io and sign up for a free account. The cloud version works fine for this.
• You get a trial with enough executions to test. No credit card needed for the trial.
• Open the workflow editor. You will see a blank canvas.

Step 2: Add a Manual Trigger (1 minute)

Search for "Manual Trigger" in the node panel. Drag it onto the canvas. This lets you start the workflow with a click instead of waiting for a webhook or schedule.

Step 3: Add an HTTP Request node (5 minutes)

Add an HTTP Request node. Set the method to GET. For the URL, paste the blog post URL you want to summarize. This fetches the page content. If the page is behind authentication, you will need to add headers. For public pages, GET works.

Step 4: Add an AI node (5 minutes)

Add a "Basic LLM Chain" node (or "AI Agent" if you want tool access). Connect your OpenAI credentials (Settings, Credentials, add OpenAI API key).

In the prompt field, write something like:

Summarize this blog post into 3 social media captions: one for LinkedIn (professional, 150 words), one for Twitter (punchy, 280 characters), one for Instagram (casual, with hashtag suggestions). Return them as JSON with keys: linkedin, twitter, instagram.

Feed the HTTP Request output into the AI node as the content to summarize.

Step 5: Add a Google Sheets node (5 minutes)

Add a Google Sheets node. Connect your Google account. Set the operation to "Append Row." Map the AI output to columns in your sheet: LinkedIn caption in column A, Twitter in column B, Instagram in column C.

Step 6: Test it (5 minutes)

Click "Execute Workflow." Watch each node light up as data flows through. Check your Google Sheet. You should see three captions appear.

If something fails, click the failing node and check the input and output. The most common issues: wrong API key, sheet column names do not match, or the blog post URL returned HTML instead of text.

Step 7: Schedule it (optional, 4 minutes)

Replace the Manual Trigger with a Schedule Trigger. Set it to run daily at 9am. Now your workflow runs automatically every morning. New blog post goes live overnight, and captions are ready by breakfast.

What to build next

Once this workflow runs, you have the foundation. From here you can add branches (different prompts for different platforms), error handling (retry on API failures), or notifications (send the captions to Slack for review before posting). Each addition follows the same pattern: add a node, connect it, test it. For a broader comparison of automation platforms, see my n8n vs Zapier vs Make breakdown. And for more quick wins, I listed 5 marketing tasks you can automate this week.