Don't Install if You Don't Have a Spare Mac
While macOS betas can be used on a primary device, we highly recommend using the software on a secondary device if you have one. Apple agrees.
In its Beta FAQ Apple "strongly" recommends installing beta software on secondary devices rather than primary ones.
If you really want to try macOS Monterey and you only have one Mac available, you should consider installing the beta on a partition or an external hard drive.
If you can't install the beta on a second Mac or on a partition so that you can easily get back to macOS Big Sur, you should probably avoid the beta.
You can downgrade to macOS Big Sur, but it's a fairly involved process and you don't want to be dealing with it if you're in the middle of a busy work week.
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