Download macOS 10.14 Mojave from the Mac App Store. Once downloaded, you can find the installer at
/Applications/Install macOS Mojave.app. Afterwards, launch the Terminal app from the
To create the install disk, execute this command:
sudo "/Applications/Install macOS Mojave.app/Contents/Resources/createinstallmedia" --volume /Volumes/Untitled --nointeraction --downloadassets
Untitled is the name of the destination volume, i.e. your USB flash drive. Enter your macOS password to
proceed. Sit back, the installer will take a while.