It can be done. If you start a fresh installation but do not go beyond the initial welcome pages of the OS X install (i.e. don't actually get to the actual installing process) then you can attach a USB connected drive having the system you want to clone on it. Parallels will ask you if you want the USB drive to be connected to the host or the guest OS. Once it is available to the guest OS you can then go to the Utilities tab within your OS X installer and select "Disk Utility" and from there you can clone from the USB drive to your virtual drive.
Once the clone is finished you can then exit Disk Utility, exit the installer and reboot your machine into the cloned version on the VM.
Alternatively you can use the Migration Assistant to get your data across to a fresh parallels install. I.e. do your installation of OS X into a parallels VM. Then attach your desired startup disk to the VM via USB and use Migration Assistant (inside the Utilities folder) to get your stuff onto the fresh install.
Last edited: Apr 26, 2016
