1. Click domains at the top of the screen. Then select add domain

2. Select the type of reports you would like to process. By default Aggregate and Failure reports are processed. For GDPR compliance select failure reports. 

3. Start the wizard

4. Copy the DMARC text report and create an _dmarc.domain.com txt record in dns

If you selected just DMARC and not MTA-STS you are now complete. Typically the first reports will take about 24 hours to process, and at that time your account status will change to green.