createinstallmedia: command not found
I use following method.


Format the USB:


Format it, using Disk Utility, as a Mac OS Extended (Journaled) drive, named Yosemite. 

Next run this in Terminal where you can remove the option —nointeraction if you want to get notifications and make decisions yourself about the disk and making the USB installer:

sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ Yosemite.app —nointeraction



Replace Untitled with name of the USB drive (Yosemite)





For additional information, see: Create a bootable installer for OS X