Connect the external hard drive to your Mac.Unless you’re 100% sure that your external hard drive is freshly formatted based on the above-described requirements, we recommend you go through the following preparation steps: More specifically, it must be at least 64 GB large (the more storage space you have, the better) and formatted using the GUID partition scheme and the APFS file system (Mac OS Extended is no longer supported)
EXTERNAL HARD DRIVE FOR MACBOOK AIR 2015 INSTALL
To successfully install macOS on an external drive, the drive you want to use must be suitable for the task ahead. Just being curious and wanting to learn something new and potentially useful is the best reason you can have. Of course, you don’t actually need a good reason to install macOS Monterey on an external drive.
EXTERNAL HARD DRIVE FOR MACBOOK AIR 2015 HOW TO
By learning how to install macOS on an external hard drive, you can safely test everything macOS 12 Monterey has to offer while preserving your current installation intact.