You now have a bootable Yosemite install drive. (see the screenshot above), which could take as long as 20 or 30 minutes, depending on how fast your Mac can copy data to your destination drive. Wait until you see the text Copy Complete. The program then tells you it’s copying the installer files, making the disk bootable, and copying boot files. The Terminal window displays the progress of the process, in a very Terminal sort of way, by displaying a textual representation of a progress bar: Erasing Disk: 0%… 10 percent…20 percent… and so on.Type your admin-level account password when prompted, and then press Return.Paste the copied command into Terminal and press Return. Warning: This step will erase the destination drive or partition, so make sure that it doesn’t contain any valuable data.Launch Terminal (in /Applications/Utilities).

Select the text of this Terminal command and copy it: sudo /Applications/Install OS X Yosemite.app/Contents/Resources/createinstallmedia -volume /Volumes/Untitled -applicationpath /Applications/Install OS X Yosemite.app -nointeraction.

This means that if you moved it before installing Yosemite, you need to move it back before making your installer disk. (The Terminal command used here assumes the drive is named Untitled.) Also, make sure the Yosemite installer, called Install OS X Yosemite.app, is in its default location in your main Applications folder (/Applications).

Connect to your Mac a properly formatted 8GB (or larger) drive, and rename the drive Untitled.

Using the createinstallmedia command in Terminal Here are the required steps: This tutorial to properly format the drive.) Your OS X user account must also have administrator privileges. That drive must also be formatted with a GUID Partition Table. Whichever method you use, you need a Mac-formatted drive (a hard drive, solid-state drive, thumb drive, or USB stick) that’s big enough to hold the installer and all its data-I recommend at least an 8GB flash drive. The Disk Utility-via-Terminal approach is for the shell junkies out there. The Disk Utility method is the way to go for people who are more comfortable in the Finder (though it does require a couple Terminal commands), and it works under Snow Leopard, Lion, Mountain Lion, Mavericks, and Yosemite. (Note that the createinstallmedia tool doesn’t work under OS X 10.6 Snow Leopard-it requires OS X 10.7 Lion or later.) The createinstallmedia method is the easiest if you’re at all comfortable using Terminal, it’s the approach that I recommend you try first. I’ve come up with three ways you can create a bootable OS X install drive for the Yosemite: using the installer’s built-in createinstallmedia tool using Disk Utility or performing the Disk Utility procedure using Terminal.

Create the Yosemite install drive: The options

Osx create bootable usb