I have a 2012 Macbook Air, currently running the latest Mountain Lion release. Is it possible to create a second partition that also runs Mountain Lion? The reason I want to do this is so that I can test software without messing around with my main primary partition. I created a second partition using disk utility but when I tried to select it to install Mountain Lion (after rebooting and pressing command R) it just said that the disk cannot be used. Any ideas?