For those registered developers who are looking to create a second bootable partition on their computer onto which to install OSX Yosemite – here are two earlier blogs that cover it.
Create a Second Bootable OSX Partition
https://skills421.wordpress.com/2013/10/29/create-a-second-bootable-osx-partition/
Create a Bootable USB to install OSX
https://skills421.wordpress.com/2013/10/29/create-a-bootable-usb-to-install-osx/
Better Yet!
Check out this Yosemite Video…