When updating old content for SEO, you should review and update your keywords, taking into account current search trends and user intent. Incorporate long-tail keywords, semantic keywords, and natural language in your content. Additionally, create a catchy and descriptive title that includes your main keyword and matches the user's query. Write a compelling meta description to summarize your content. Improve the quality and readability of your content by correcting spelling, grammar, and punctuation errors, rewriting vague or redundant sentences, using active voice, short paragraphs, and transitions. Add subheadings, bullet points, images, videos, or other elements to break up the text. Verify that your facts, data, and sources are accurate and current by updating any outdated or incorrect information. Cite credible sources to back up your claims and link to relevant external and internal pages. Finally, add a call to action to encourage visitors to take the next step after reading your content. Use clear and persuasive language and place the call to action in a prominent location.