In order to create a bootable copy of the OS X Mavericks installer, you must locate the InstallESD.dmg file that's hidden in the OS X Mavericks installer you downloaded. This image file contains a bootable system and the files necessary to install OS X Mavericks.
Since the installer image file is contained within the OS X Mavericks installer app, we must first extract the file and copy it to the Desktop, where we can then easily make use of it.
- Open a Finder window and navigate to your Applications folder.
- Look through your list of applications and locate the one named Install OS X Mavericks.
- Right-click or control-click the Install OS X Mavericks file and select Show Package Contents from the pop-up menu.
- The Finder window will display the contents of the Install OS X Mavericks file.
- Open the Contents folder.
- Open the SharedSupport folder.
- Right-click or control-click the InstallESD.dmg file, and then select Copy "InstallESD.dmg" from the pop-up menu.
- Close the Finder window, and return to your Mac's Desktop.
- Right-click or control-click on an empty area of the Desktop and select Paste Item from the pop-up menu.
- The InstallESD.dmg file will be copied to your Desktop. This can take a bit of time, because the file is around 5.3 GB in size.
When the process is finished, you'll find a copy of the InstallESD.dmg file on your Desktop. We'll use this file in the next series of steps.