Scroll down and double click on Terminal. Important:You will need to be in your Mac's administrator account in order to run the sudo Terminal command. Your thumb drive or external hard drive is now ready. Click Done when the process is complete.If Scheme is available, select GUID Partition Map.Select Mac OS Extended (Journaled) from the format list.Rename your external hard drive MyVolume.Scroll down and double-click on Disk Utility.Ĭlick on the Erase tab at the top of the window. Scroll down and double-click on Utilities.Select Applications from the list on the left side of the window. Click on Finder in your Dock to open a Finder window.Plug the USB end of the drive to a USB port on your Mac.You'll need to start with a clean thumb drive or hard drive in order to get it ready to work as a bootable drive. How to format your external drive for Mac
