Terminal doesn't show any characters as you type your password. When prompted, type your administrator password and press Return again.* If your Mac is using macOS Sierra or earlier, include the -applicationpath argument and installer path, similar to the way this is done in the command for El Capitan.
Sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia -volume /Volumes/ MyVolume -applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app Sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia -volume /Volumes/ MyVolume Sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia -volume /Volumes/ MyVolume Sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia -volume /Volumes/ MyVolume Sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia -volume /Volumes/ MyVolume If it has a different name, replace MyVolume in these commands with the name of your volume. These assume that the installer is in your Applications folder and MyVolume is the name of the USB flash drive or other volume you're using.
