In April, I wrote an article on TechRepublic about how to create a bootable USB to install OS X. The latest iteration of OS X, version 10.9 (aka Mavericks), marks not only 200+ changes in the OS, but also does away with the fabled “big cat” naming scheme. However, the focus of this article is the change in the process for creating a working, bootable USB drive.

Creating a USB Installer for Apple OS X 10.9

Before proceeding, you’ll need the following items to complete the process:

  • 8 GB USB Flash Drive (or SD Card)
  • Install OS X (installer downloaded from Mac App Store)
  • Apple computer with Mac App Store (OS X 10.6.8+)
  • User Account with Administrative privileges

Follow these steps:

  1. Using a Mac with at least OS X 10.6.8 installed, access the Mac App Store and download the Mavericks (10.9) app installer
  2. Insert the USB drive into the Mac and launch Disk Utility
  3. Click on the USB drive from the left-hand menu and select the Partition tab
  4. Click the drop-down menu, selecting 1 partition
  5. Select Mac OS Extended (Journaled) for the format-type from the drop-down menu (Figure A)
  6. Click on the Options button, select the radio button for GUID Partition Table, and click OK (Figure B)
  7. Launch the by selecting it from the /Applications | Utilities folder and execute the following command (Figure C)*:

    defaults write AppleShowAllFiles TRUE;\killall Finder;\say Files Revealed

  8. Upon completion of the USB formatting, locate Install Mac OS X (downloaded in step #1 to the Applications folder, by default). Right-click the file and select Show Package Contents (Figure D)
  9. Navigate the file structure Contents | Shared Support and double-click the InstallESD.dmg file mount OS X Install ESD on the desktop (Figure E)
  10. Double-click the mounted .dmg file and locate the hidden BaseSystem.dmg (Figure F)
  11. Go back to Disk Utility and click on the newly formatted USB Drive in the menu, then click on the Restore tab
  12. Drag the BaseSystem.dmg over to the Source text box. For Destination, drag and drop the partition created on the USB drive onto the textbox (Figure G)
  13. Upon verifying that the fields are correct, click the Restore button and select Erase from the application, if prompted to do so (Figure H)
  14. The process may indicate in excess of one hour, but in my experience, the process takes significantly less time to complete (Figure I)
  15. Once the files have finished copying over, the drive should mount automatically. Navigate the file structure to System | Installation and delete the alias to the Packages directory (Figure J)
  16. Going back to the mounted Install ESD.dmg file on the desktop (step #10), locate the directory named Packages and copy it to the directory in step #15 (Figure K)

There you have it — a bootable copy OS X Mavericks on USB Flash Drive that can be used to install, upgrade, and/or troubleshoot compatible Apple computers. The process has become a bit more cumbersome, but once all the files are in their proper place, the USB drive works much the same. Simply insert your drive, power on the computer, and hold down the Option key to access the boot selection menu. From there, select the USB drive partition and press enter to initiate the boot process.