How to install MacOS
I've just replaced the original 1TB HD with a 2TB SDD drive in a Late 2009 iMac 27 inch. Essentially I now have a blank HD so I'd like to know how to install the MacOS ? I did the startup holding down Command-R but of course just got a Folder icon with flashing '?' as there has never been an OS on the drive.
I have access to a MacBook Pro & DVD drive so I could make a boot disk if this was the right course of action but I'd need step-by-step instructions if this is the best course of action