Once the process completes, you will see the message 'Copy Complete. Do not interrupt the Terminal or eject the flash drive during the process. This will create the bootable USB flash drive.Sudo /Applications/InstallOSXYosemite.app/Contents/Resources/createinstallmedia -volume /Volumes/YosemiteInstaller -applicationpath /Applications/InstallOSXYosemite.app -nointeraction Launch the Terminalapp (in Applications/Utilities) and copy-paste the following command in, and then hit Enter:.Click on Option and ensure GUID Partition Table is selected as the partition scheme, with its name set to YosemiteInstaller. Then choose Partition tab and select 1 Partition from Partition Layout dropdown menu.Now click on Erase button and wait until the format process completes.Choose Mac OS Extended (Journaled) in the format box and set the name be YosemiteInstaller.Select the USB drive from the left sidebar and click on Erase tab.Plug in your USB drive into the computer and open Disk Utility (in Applications).Once it's downloaded, just quit the installer and set the downloaded file's name to InstallOSXYosemite.app (make sure only. (a USB3 one will be much quicker).įirst download the OS X 10.10 Yosemite installer from the Mac App Store in the Purchases section (you may need to hold alt/option while selecting Purchases. If not, then you'll need to make a Yosemite USB installer of at least 8GB. If you have a Time Machine backup, you need this support page:

Yosemite usb installer