As far as I've heard you need an external hard drive. Do I just connect my External, bootup my mac with the 10.X disc, and the external should be there to be selectable? or is it more complicated?
should be firewire, its partition should be guid(if it is an intel mac, otherwise it should be apple partition-check disk utility) and i dont't know if it makes a difference but it should be set as bootable. i did the last thing with superduper, while cloning my main hd.