To avoid being listed on an RBL, adhere to best practices in email marketing:
1. Ensure you have permission from recipients before sending emails. 2. Regularly clean and update your email list to remove invalid or inactive addresses. 3. Monitor your email metrics, such as bounce rates and spam complaints. 4. Implement authentication protocols like SPF, DKIM, and DMARC. 5. Use a reputable email service provider (ESP) that has good deliverability practices.