How do I register for Google Analytics?

In the case of the Minimal Mistakes theme, simply paste tracking ID in the [config.yml](https://github.com/mmistakes/minimal-mistakes/blob/master/_config.yml#L97) file. 

```
# Analytics
analytics:
  provider               : "google-gtag"
  google:
    tracking_id          : "Tracking ID"
    anonymize_ip         : # true, false (default)
```

How do I do it in this theme?