Partition a 16 GB USB Drive into two volumes. Make each volume a bootable OS X Installer for two different versions, in this example Yosemite and Mavericks.

Erase:
Using Disk Utilities, erase the USB using Mac OS Extended (Journaled).

Partition:
Set each to Mac OS Extended (Journaled)
Take out the space in “Untitled1” and “Untitled2″ Continue reading →