Run the macOS Developer Beta Access Utility to download the latest macOS beta. As new macOS betas become available you will receive a notification and can install them from the Software Update pane in System Preferences.
With macOS Catalina, Apple is replacing iTunes with new Apple Music, Apple Podcasts and Apple TV apps. A new Sidecar feature enables users to extend their Mac desktop by using their iPad as a second display or as a high-precision input device. New security features keep users better protected and Voice Control lets users control their Mac entirely with their voice. You can learn more about macOS Catalina here.
Developers can download the Beta Access Utility from the link below. The public release of macOS Catalina is schedule for next month. Please follow iClarified on Twitter, Facebook, Google+, or RSS for updates.