USB 隨身碟的容量必須要有 8 GB (含)以上
首先要有安裝包，例如: Install macOS Mojave.app (預設從 AppStore 下載會放在 /Applications 目錄下)
在安裝包所在路徑執行以下指令以建立可開機安裝 USB 隨身碟 (假設 USB 隨身碟掛載路徑在/Volumes/USB )
$ sudo ./Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/USB --downloadassets
Ready to start.
To continue we need to erase the disk at /Volumes/USB.
If you wish to continue type (Y) then press return: Y
Erasing Disk: 0%... 10%... 20%... 30%...100%...
Finding assets to download...
Downloading assets: 0%... 10%... 20%... 30%... 40%... 50%... 60%... 70%... 80%... 90%...
Copying to disk: 0%... 10%... 20%... 30%... 40%... 50%... 60%... 70%... 80%... 90%... 100%
Making disk bootable...
Copying boot files...
Install media now available at "/Volumes/Install macOS Mojave"