How to Create a USB macOS X Installer Drive


For those who wish to perform a clean install of macOS X using a bootable USB drive.


Acquiring the OS from the App Store

  1. From the Apple menu, select the App Store…
  2. Select Featured at the top bar
  3. At the lower right-hand side under All Categories, click OS X Yosemite
  4. Click the Download button
  5. At the confirmation drop-down window, click the Continue button to begin the download
    Note: This is a 5.17GB download and might take some time to complete, depending on your bandwith and the activity of the server. To see the progress, you can examine the Launchpad on the Dock.
  6. After the download completes, the Install OS X Sierra application auto-launches.
  7. From the Install OS X menu, select Quit Install OS X.

Preparing the USB Drive

  1. Plug the USB drive into a USB port on your computer.
  2. Launch Disk Utility, by navigating to Applications > Utilities
  3. Click on the device (not the volume) that represents your USB drive
    Note: You should see a list of devices and their related volumes in the left pane.
  4. In the menu bar click on the Erase button
  5. In the Name: field verify or set Name to Untitled
  6. Click on the Format: pull-down menu and select Mac OS Extended (Journaled)
  7. Click on the Scheme: pull-down menu and select GUID Partition Map
  8. Click on the Erase button
    Note: If you experience an initial failure just go back to step 4 and try again.
  9. From the Disk Utility menu, select Quit Disk Utility

Placing the OS X Installer and Making the USB Drive Bootable

  1. Launch the Terminal, by navigating to Applications > Utilities.
  2. Type the following command: sudo /Applications/Install OS X –volume /Volumes/Untitled –applicationpath /Applications/Install OS X –nointeraction
  3. After the process completes, type the following command: exit
  4. From the Terminal menu, select Quit Terminal
  5. Right-click on the new Install OS X Yosemite USB drive icon on the desktop then from the contextual menu and select Eject “Install macOS Sierra”