Gym owners can retain new members by communicating effectively with them, which can be achieved through regular emails or texts from coaches and staff using shared email apps like Front. With the help of automation tools like Zapier, gyms can create custom workflows that streamline communication, reduce no-shows, and improve overall customer experience. By automating tasks such as sending appointment reminders, logging customer interactions, and creating a database of customer interactions, gyms can increase efficiency, reduce manual work, and provide better service to their members.