Making a bootable HD
How do I make a bootable disk which I can load OS Big Sur to to update my firmware?
Want to highlight a helpful answer? Upvote!
Did someone help you, or did an answer or User Tip resolve your issue? Upvote by selecting the upvote arrow. Your feedback helps others! Learn more about when to upvote >
Did someone help you, or did an answer or User Tip resolve your issue? Upvote by selecting the upvote arrow. Your feedback helps others! Learn more about when to upvote >
How do I make a bootable disk which I can load OS Big Sur to to update my firmware?
Follow How to reinstall macOS - Apple Support and designate the external disk as its destination.
Big Sur may not be the version it offers. Use the applicable key chord as described in Other macOS installation options. You may, for example, need to install an older version followed by upgrading macOS to Big Sur. To do that, read How to download macOS - Apple Support. Once downloaded to your Mac, install it on the external disk the same way.
... to update my firmware?
That part of your question needs explanation. Mac firmware becomes updated with macOS updates and upgrades.
Follow How to reinstall macOS - Apple Support and designate the external disk as its destination.
Big Sur may not be the version it offers. Use the applicable key chord as described in Other macOS installation options. You may, for example, need to install an older version followed by upgrading macOS to Big Sur. To do that, read How to download macOS - Apple Support. Once downloaded to your Mac, install it on the external disk the same way.
... to update my firmware?
That part of your question needs explanation. Mac firmware becomes updated with macOS updates and upgrades.
Making a bootable HD