UPDATE 09/2018: Create a Bootable macOS Mojave Install Drive with DiskMaker X 8 UPDATE 09/2017: Create a Bootable macOS High Sierra Install Drive with DiskMaker X 7 Apple has made macOS installations (and those for Mac OS X before it) as simple.
DiskMaker X is a practical tool developed with AppleScript that lets you copy an install file for the OS X Yosemite operating system to a USB drive so you can turn it into a boot disk during startup. To make the copy, you just have to install the DiskMaker X application on your computer, download a copy of Yosemite, and follow the assistant's steps to set it up. You must have a USB drive with at least 8 gigabytes of space and free of important files since the memory will have to be completely reformatted to make a copy of the operating system. If all goes well, after a few minutes, you'll have a Yosemite installer on the USB drive that you can then use to install a clean copy of the operating system on your Mac. Its own developers describe it as the easiest way to create a boot disk for OS X. What's more, this tool is not only useful for Yosemite but also supports the Mavericks and Mountain Lion installers as well.
How to create a macOS Catalina installer using DiskMaker X.In order to create this you will need to be running macOS Mojave.i'm not sure if you can create th.
Launch the DiskMaker X installer and in the disk image window that appears, drag the application.
At the moment, DiskMaker X provides support for Mac OS X 10.9, 10.10, and 10.11. The DiskMaker X main panel where you must choose the OS X version for which you want to make a bootable disk.
Notes
Diskmaker X For Snow Leopard
Mac OS X 10.6x or higher is required to run this application.