Should you (or a colleague) ever find yourself in a situation where macOS requires restoring, in a pinch, the USB installer can be used to reinstall (and/or upgrade to) macOS on-the-fly. Much like users that work remotely or in hybrid environments have grown accustomed to bringing the accessories they need with them that allow them to be their most productive, a small tool that many mobile users carry with them already and about twenty minutes of time is all that’s necessary to create your very own USB installer drive with the latest version of macOS on it.

The reasons for this occurring may vary, but what is certain is that being left stranded without your Mac when you need it most and without access to online resources or IT to get it restored doesn’t have to be the dreadful situation it sounds like with a little preparation. If Murphy’s Law has anything to say about it, there might be times that require us to upgrade or worse, restore macOS, when internet access is spotty or simply unavailable. You can now quit Terminal and eject the volume.While upgrade deployments work best when planned, we don’t always get to choose when life will happen.

When Terminal says that it's done, the volume will have the same name as the installer you downloaded, such as Install macOS Monterey.After the volume is erased, you may see an alert that Terminal would like to access files on a removable volume.Terminal shows the progress as the volume is erased. When prompted, type Y to confirm that you want to erase the volume, then press Return.Terminal doesn't show any characters as you type. When prompted, type your administrator password.If the volume has a different name, replace MyVolume in the command with the name of your volume. Each command assumes that the installer is in your Applications folder, and MyVolume is the name of the USB flash drive or other volume you're using. Type or paste one of the commands below into Terminal, then press Return to enter the command.

Open Terminal, which is in the Utilities folder of your Applications folder.

Plug in the USB flash drive or other volume that you're using for the bootable installer.

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