I have been trying to figure out a way to install Mavericks/Yosemite from a bootable USB thumb drive into VMware Fusion v6.0.5. I searched around and everything that I read said that it was not supported. Someone may have posted something but as of today, I have not found it. Plus, there could be an easier way than what I found. Anyway, hope this works for you.
BTW, I am assuming some familiarity with Fusion. I am also assuming you already have a bootable USB installable drive.
Lastly, there are much easier ways to install Mavericks/Yosemite if you are not limited to an Internet connection. However, if you work in an environment where you cannot use the Recovery Method and you cannot for what ever reason get access to the Internet, then this method is for you.
Installing Mac OS X Mavericks/Yosemite from a bootable USB thumbdrive into VMware Fusion:
Chad S. Hayes 