Installation – GTM
Best practice as of this moment is to have both Ga4 and UA installed.
Choose Platform -> Website.
Enhanced Measurement -> Yes!
Stream -> Where Data Comes from
GTM Installation -> Do it the same way as you do with GA3
To Install GA4
- Connected Site Tags (Gtag.js) – if you have UA installed by the gtag js, you can share this tag and link it to GA4

- GTM Way (Recommended) – you install separate instances of UA and GA4


Debug Mode
You can test your GA4 implementation in two ways:
- GTM Preview Mode
- Google Debugger Extension