Here’s how to setup a conversion-based on an existing page view type (like a /thank-you page)…
#1 Setup GA4 event tag in Google Tag Manager
NOTE: Conversions can actually be setup within GA4 using existing specific page views, but I’ve found that these can over-count. However, setting these up in GTM, you have the option of firing the tag once per page, rather than once per event.
* Setup a new tag in GTM: ‘Google Analytics: GA4 Event’
* Select configuration tag: You can use the existing GA4 tag you have in GTM for this, or select ‘None – manually set ID’, and enter your measurement ID (GA4 > Settings > Data Streams > Click on a data stream)
* Give your event a name – something descriptive you’ll understand in GA4’s reports. Replace spaces with underscores. E.g. enquiry_form_complete
* (optional) Add any parameters you’d like to send in with the event – e.g. page path, or any other variables / stuff in the dataLayer
* IMPORTANT: If you only want this conversion to fire once per page, which is how page view conversions work currently in Universal Analytics, then you need to set this tag to fire once per page – Advanced settings > Tag firing options > Once per page
* Setup a trigger to fire this tag on the page views you want it to fire on – e.g. Page View trigger type, when the page path contains ‘/thank-you’
* Save the tag. Preview it to make sure it fires, and fires the correct values (in Google Tag Assistant)
* Submit and publish it