To formulate a GDPR-compliant text on your newsletter, you should: 1. Inform the recipient that you are processing their personal data under the GDPR. 2. Specify what type of personal data is collected and how it is used. 3. Explain the recipient's rights under the GDPR, such as the right to request access to, rectification or erasure of their personal data. 4. Include contact information for the person responsible for data protection in your organization.