You will need to have a free Pinterest Business account.
1) You will need to have the Yoast SEO plugin installed. This only work’s with self-hosted WordPress blogs, so to sign up for that read this article. If you already have a self-hosted blog, go to your yourblogname.com/wpadmin page, plugins, add new, Search yoast SEO and install.
2) Once that is installed so to ‘dashboard’ and ‘features’ and where is say’s “advanced setting page” make sure it is enabled!
3) A list of new features will appear, so go on social and make sure “add open graph meta data” is enable in the Facebook tab.
4) Go to the Pin validator and type in the URL to one specific blog post, and click ‘apply now’
5) That’s it! A message like the one above will pop up, and then you will get an email (sometimes it takes a while, other times it is pretty instant) and now when you pin items from your website it will automatically be a rich pin.