DiskMaker X 9 for macOS Catalina

DiskMaker X can be used to build a bootable drive from OS X/macOS installer program. As soon as you launch the application, it tries to find the OS X Install program with Spotlight.

Then, it proposes to build a bootable install disk. You can use the Install drive to fully re-install the OS on a freshly formatted drive, or install it on your many Macs without re-downloading the full installer.