To build a Python-based booking system for services like Bookable, start by defining your requirements—such as user management, booking schedules, and payment integration. Use Flask or Django to set up your web framework. Implement models to handle data related to users, services, and appointments. Develop views and templates for the user interface, and include forms for booking and payment processing. Integrate a database like SQLite or PostgreSQL for data storage. Finally, test your system thoroughly to ensure it handles bookings correctly and securely. Deploy the application to a web server or cloud service to make it accessible to users.