Google Analytics 4 (GA4) is quick to install – but rarely set up properly. Missing consent logic, unfiltered internal traffic or undefined key events mean the numbers tell you very little. This guide walks you through the key steps for a clean foundation.
What is GA4 and why does the setup matter so much?
GA4 is the current version of Google Analytics and measures user interactions on websites and apps as events. Unlike the former Universal Analytics, GA4 isn’t built on sessions and pageviews but on a flexible event-based model.
The setup determines your data quality: anything you don’t configure correctly at the start usually can’t be fixed retroactively.
Step 1: Create a property and data stream
A GA4 property is the container for all of your website’s data; the data stream connects the property to your website. Create both in the Google Analytics admin area.
- Set the time zone and currency correctly (e.g. Europe/Berlin and euro) – this affects every report.
- Create a web data stream with the correct domain.
- Note down the Measurement ID (it starts with “G-”) – you’ll need it for the installation.
Step 2: Install the tag – ideally via Google Tag Manager
We recommend installing via Google Tag Manager (GTM), because it lets you manage tags, triggers and consent logic centrally. Alternatively, you can add the Google tag directly to your source code.
In GTM, you create a Google tag with your Measurement ID and fire it on all pages – but only once your consent logic is in place (see step 3).
Step 3: Data protection and Consent Mode
In the EU, you generally may only use GA4 after visitors have given their consent. For that, you need a consent management tool (cookie banner) and should implement Google Consent Mode v2 correctly.
Clarify the following points with your data protection officer or legal advisor – this article is not legal advice:
- Cookie consent: GA4 sets cookies and processes usage data. A consent banner must obtain consent before analytics cookies are set – with an equally prominent reject option.
- Consent Mode v2: It passes the consent status (including
analytics_storage,ad_storage,ad_user_data,ad_personalization) to Google tags. In “Basic” mode, tags only load after consent; in “Advanced” mode, cookieless signals are sent without consent. Which option suits you is also a data protection decision. - Data processing agreement: Accept Google’s data processing terms in the GA4 admin area. They serve as the data processing agreement (DPA) with Google.
- IP addresses: According to Google, GA4 does not log or store IP addresses; manual IP anonymization as in Universal Analytics is no longer necessary. IP addresses are still processed briefly to determine location – this belongs in your privacy policy.
- Privacy policy: Describe the purpose, legal basis, recipients, possible transfers to third countries and retention period.
Step 4: Key settings in the admin area
You should adjust some of GA4’s default settings right after creating your property so your data is complete and clean.
| Setting | Recommendation | Why |
|---|---|---|
| Data retention | choose deliberately (2 or 14 months) | default is 2 months; affects explorations |
| Internal traffic | define your own IP ranges and activate the filter | otherwise distorts visitor numbers |
| Unwanted referrals | add payment providers and similar | prevents incorrect source attribution |
| Google signals | only after review and with appropriate consent | relates to personalized advertising |
| Enhanced measurement | enable and review the events | scrolls, downloads, outbound clicks |
Tip: Create the internal traffic filter in “Testing” state first and check it before activating – filtered data cannot be recovered.
Step 5: Define key events
Key events (formerly “conversions”) are the actions that really matter for your business. Without them, GA4 measures visits but not your success.
Typical key events for service businesses and shops:
- Submitting a contact form (ideally via a thank-you page or a dedicated event)
- Clicking a phone number or email address
- Booking an appointment
- Purchase (
purchase) with revenue value in e-commerce - Downloading a guide or price list
Only mark actions with real business value as key events. Ten “key events” for every scroll dilute your analysis.
Step 6: Set up integrations
Linking GA4 to other Google services significantly expands what you can analyze.
- Google Ads: Import key events for bid optimization and use audiences for remarketing (only with appropriate consent).
- Google Search Console: Shows you organic search queries directly in GA4.
- BigQuery (optional): For raw data export and deeper analysis.
Step 7: Test before you rely on the data
Test every part of your setup before making decisions based on the data. Otherwise, errors often only surface weeks later.
- GTM preview mode and Tag Assistant: Do the tags fire correctly – including depending on consent?
- DebugView in GA4: Do events arrive with the right parameters?
- Realtime report: Can you see your own test visit?
- Consent test: Are analytics cookies really not set without consent?
Checklist: Is your GA4 set up properly?
- Property with correct time zone and currency
- Data stream created, tag installed via GTM
- Consent banner and Consent Mode v2 implemented and tested
- Data processing terms accepted, privacy policy updated
- Data retention set deliberately
- Internal traffic filtered, unwanted referrals added
- Key events defined and tested
- Google Ads and Search Console linked
Conclusion
A clean GA4 setup is the foundation for every data-driven marketing decision – from allocating your Google Ads budget to evaluating your SEO work. Take the time for consent logic, filters and key events, and test everything before you rely on the numbers. If you’d like help with the setup or a review of your existing tracking, take a look at our tracking services or get in touch with us directly.