1. Identify and Remove Duplicates: Use tools to find and eliminate duplicate entries. 2. Validate Email Addresses: Ensure that all email addresses in your list are valid and correctly formatted. 3. Update Outdated Information: Regularly update contact information to keep it current. 4. Remove Inactive Subscribers: Identify subscribers who have not engaged with your emails for a certain period and consider removing them. 5. Segment Your List: Segmenting your list can help in targeting the right audience and reducing the chances of sending irrelevant emails.