- SPF Setup: Add a TXT record with a value that specifies which IP addresses or domains are permitted to send email on behalf of your domain. Example: `v=spf1 include:_spf.example.com ~all`. - DKIM Setup: Generate a DKIM key and add it as a TXT record. The key is usually provided by your email service provider. - DMARC Setup: Create a TXT record with the DMARC policy. Example: `v=DMARC1; p=none; rua=mailto:dmarc-reports@example.com`.