Once you've downloaded the Mac OS Sierra 10.12 DMG file, follow these steps to install it:
To install Mac OS Sierra 10.12 from the DMG file: Download Mac Os Sierra 10.12 Dmg
Open and enter the following command: sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ macOS\ Sierra.app Once you've downloaded the Mac OS Sierra 10