You can add a Google Analytics URL in your settings by going to https://mirror.xyz/dashboard/settings and scroll down to the section titled "Google Analytics UAID" and entering your UAID.
For instructions on setting up Google Analytics, check out this guide on their website: https://support.google.com/analytics/answer/10269537?hl=en
If you have any questions, please submit a support request below and we'll get back to you.