It’s beta season for Apple developers, but it’s not a wise idea to install those betas on your main machines. Dual boot is the way. This way, you can easily switch back to your stable version of macOS if needed. I did not find an up-to-date guide to install a macOS beta in a separate APFS volume on your Mac.

Word of caution: Duncan Babbage points out: “An operating system that changes the structure of the file system isn’t constrained by the boundaries of an APFS container.” While I haven’t had issues with my main Sonoma install after installing Sequoia as below, but be mindful of this.

Here’s how to do it on an Apple Silicon Mac:

1. Backup using Time Machine
2. Create a new APFS volume
3. Shut down Mac
4. Start up and keep holding down the power button
5. Select “Options”
6. Then choose to reinstall Sonoma onto the volume from step 2.
7. Wait a while (it said 5h for me, but took <1h)
8. When it’s installed, probably best to not log into iCloud (though I did, and then disabled all the various sync options) and skip migrating your previous user account
9. Then open to System Settings, enable beta updates, and update that install to Sequoia
10. File feedback to Apple!