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How to Bootable USB for macOS
1. Confirm the complete “Install macOS Mojave.app” installer file is located in the /Applications directory
2. Connect the USB flash drive to the Mac Min 16 GB, than use disk utility and erase usb volume and create Mac OS Extenden Journaled set usb name Mojave
3. Launch the Terminal ( Command + Space type Terminal hit enter) than copy and paste below code,
4. sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/Mojave --nointeraction && say Mojave Drive Created
Success
How to Boot from USB
✓ Reboot Mac than hold OPTION (alt) key and select Mojave installer or Open Mojave installer.app in USB