Now launch Terminal, also found in /Applications/Utilities/.Still in Disk Utility, go to “Partitions” and click ‘Options’ to set the partition table to be GUID – this is necessary to make the drive bootable.From Disk Utility, erase the USB drive to be Mac OS Extended.Launch Disk Utility from the /Applications/Utilities/ folder.When the splash screen launches, quit the installer app – DO NOT install Yosemite yet.

Download the OS X Yosemite Beta installer from the App Store (you must be a registered participant in the beta program, you can sign up to get it).

How to Build a Bootable OS X Yosemite Beta Installer DriveĬreating a bootable Yosemite beta installer uses the same createinstallmedia trick that works with OS X Mavericks bootable installers, with the only differences being in file naming. Once you have those basics met, you can create the bootable installer and then use it to get Yosemite beta running.

A Mac that can run Yosemite, which is basically any Mac that can run Mavericks.

The OS X Yosemite Beta installer app downloaded on the Mac, sitting in the /Applications/ folder (that means you downloaded the installer but have not yet used it, using the installer app automatically deletes it after completion).

8GB+ USB drive that you don’t mind formatting.

Quick side note: if you’ve been having problems downloading the Yosemite Beta, try these tips to resolve the download issues.Ĭreating an OS X Yosemite Beta bootable installer disk out of a USB key or external volume is really quite easy, and the requirements are fairly straightforward as well.

Os x yosemite download usb boot