Once you press the Return key, the installation process will begin.

For other Operating Systems, Apple provides the necessary snippets you need. Of course, you’ll need to change the file paths if neither of these are true. The downloaded installer will get stored in your Applications folder.You’re installing macOS Big Sur onto your USB drive.Note that you’ll want to change the placeholder for whatever your USB drive is called: sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia -volume /Volumes/ Open Terminal (found in the Utilities folder) and copy the snippet below. Follow the instructions below for another way to create a bootable installer.

It may open and begin to take you through the installation process when it finishes downloading, but you don’t want to do this.

Given the size of macOS Big Sur (around 13GB), it may take a while.