Sort through the file hierarchy Contents | SharedSupport and mount the InstallESD.dmg file by double-clicking it ( Figure G).Right-click the installer and select Show Package Contents from the context menu ( Figure F). Navigate to the location where the OS X 10.10.

Enter the following command ( Figure E):ĭefaults write AppleShowAllFiles 1 | KillAll Finder Launch Terminal.app to enter a command that will unhide the hidden files needed to complete the next few steps.Once completed, the removable drive will be prepped for OS X ( Figure D). Depending on the size of the drive, the changes typically take several minutes to process.Click Partition to execute the changes ( Figure C). Verify the changes to be made to the drive are correct, and then click Apply.Select the radio button next to GUID Partition Table, clicking OK to accept the change ( Figure B).Click the Options button to bring up the partition scheme menu.Enter a name for the device, and select the format as Mac OS Extended (Journaled) from the drop-down list next to Format ( Figure A).Under Partition Layout, select 1 Partition from the drop-down menu.Select the drive you wish to use from the device list and click the Partition tab.Insert the USB Flash Drive (or SD Card) into the Apple computer, and launch Disk Utility.app from the Applications | Utilities folder.With that said, follow the steps below to create a bootable USB installer: User Account with Administrative privileges.Apple computer with Mac App Store (10.6.8+).OS X 10.10 DP1.app (installer downloaded from Apple's Mac Developer site).Before getting started, let's review the requirements for creating a bootable drive:

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