You have to format and hash <email_address> using the SHA-256, SHA-1 or MD5 algorithm. <email_address> needs to be lowercase and have all spaces removed.
The formatted and hashed <email_address> has to be added to every Pinterest tag <img> tag URL on your website using the &pd[em]=<hashed_email_address> parameter. This parameter has to be added to both the base code and the event code <img> tags.
<noscript> <img height="1" width="1" style="display:none;" alt="" src="https://ct.pinterest.com/v3/?tid=<YOUR_TAG_ID>&event=<EVENT_NAME>&pd[em]=<hashed_email_address>&noscript=1" /> </noscript>
Replace YOUR_TAG_ID, EVENT_NAME and hashed_email_address with corresponding values or variables on your website.