How to Create Bootable MacOS Installation ISO 🌱

Things You Will need

Creating the Bootable .iso

  1. Download the MacOS install from the Mac App Store
    NOTE: the easiest way to find them is to use a search engine, for example:
    macos monterey
  2. Click the Get button
  3. Wait for Software Update to find the update
  4. When prompted, click Download
  5. Wait for the download to complete
  6. Once the download completes, quit the installation if its starts
  7. Start LaunchPad from the dock
  8. Search terminal > Click Terminal to launch it
  9. Run the following commands in terminal, altering the MacOS Installer name as needed
    # create temporary disk image, make sure its larger than the downloaded installer
    hdiutil create -o /tmp/macOS -size 15000m -volname macOS -layout SPUD -fs HFS+J
    # mount the temporary disk image
    hdiutil attach /tmp/macOS.dmg -noverify -mountpoint /Volumes/macOSISO
    # use createinstallationmedia utility to copy files
    sudo /Applications/Install\ macOS\ --volume /Volumes/macOSISO --nointeraction
    # unmount the temporary disk image, alter the OS name as needed
    hdiutil detach -force /Volumes/Install\ macOS\ Monterey
    # convert the disk image to .iso
    hdiutil convert /tmp/macOS.dmg -format UDTO -o ~/Desktop/macOS.cdr
    # change the extension from .cdr to .iso
    mv ~/Desktop/macOS.cdr ~/Desktop/macOS.iso