[Main Google SEO guide]{https://developers.google.com/search/docs}

{https://developers.google.com/search/docs/guides/javascript-seo-basics}[Google’s guide on JavaScript SEO basics]

Create a responsive or dynamic serving site

[Google guidelines for dynamic serving site]{https://developers.google.com/search/mobile-sites/mobile-seo/dynamic-serving}

Google uses mobile first indexing

Make sure Googlebot is not blocked by robots.txt

Make the primary content the same as those on desktop

Make a standard heading

use

instead of custom tag

Make sure data is easy to find without scrolling

This includes videos, images, and other media

Don't make anything invisible

Make sure you have meta description markup!

[Google guidelines for having separate mobile site]{https://developers.google.com/search/mobilesites/mobile-seo/separate-urls}

[Bing guidelines for mobile site]{https://blogs.bing.com/webmaster/2014/11/03/meet-our-mobilebots/}

[Use Lighthouse to check your site]{https://developer.chrome.com/docs/lighthouse/overview/}

[Use pagespeed insights]{https://pagespeed.web.dev/}

Check site speed and get recommendations:

[https://developers.google.com/speed/pagespeed/insights/]{https://developers.google.com/speed/pagespeed/insights/}

[https://www.webpagetest.org/easy.php]{https://www.webpagetest.org/easy.php}

[https://gtmetrix.com/]{https://gtmetrix.com/}

Check mobile-friendliness

[https://search.google.com/test/mobile-friendly]{https://search.google.com/test/mobile-friendly}

Crawl budget

No duplicate pages

Use robots.txt to block duplicate pages

Use JS to load duplicate pages

Make sure 301 redirects to canonical URL