Visual Visitor’s WordPress Plugin Visual Visitor has created an easy to use, WordPress Plugin.
Alternative - manual theme installation:
If you prefer not to use a plugin (or if visitors might disable unknown plugins), you can add the script manually. Open your theme's header.php file (via Appearance > Theme File Editor) and paste the script just before the closing </head> tag.
Cache plugin warning:
Many WordPress sites use caching plugins (WP Rocket, W3 Total Cache, LiteSpeed Cache, etc.). After installing the Visual Visitor script, clear your cache so the updated page code is served to real visitors. Failure to clear the cache is the most common reason a newly installed script does not appear to fire.
Verify the installation:
Visit your live site, open Developer Tools (F12 > Network), and filter for your script to confirm it is loading on each page load.