How to Use an External HDD as a Bootable Drive With a MacBook
- 1). Install Mac OS X on an external drive. Do this using the Apple system discs that came with your MacBook, or you can use software such as Carbon Copy Cloner to duplicate your internal drive.
- 2). Connect the external drive to your MacBook using the appropriate cable.
- 3). Restart your MacBook, or turn it on if it's off.
- 4). Press and hold the "Option" key on the keyboard. Wait a few seconds. The Startup Manager checks for available volumes and then appears on the screen.
- 5). Press the left and right arrow keys on your keyboard to select a volume. Select your external hard drive.
- 6). Press the "Return" key on your MacBook keyboard. This starts the computer from the external volume you selected.
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