To implement DMARC reporting, you need to add a DMARC record to your DNS. This record includes the policy for handling failed emails and the email addresses where you want to receive the reports. Here's a basic example of a DMARC record:
_dmarc.example.com. IN TXT "v=DMARC1; p=none; rua=mailto:dmarc-reports@example.com; ruf=mailto:dmarc-forensic@example.com; pct=100"
In this example, rua specifies the email address for aggregate reports, and ruf specifies the email address for forensic reports.