How do I create a second bootable macOS volume?

You may need a second macOS installation to run disk utilities, manage SoftRAID volumes, or troubleshoot your main system. APFS containers allow you to create additional bootable volumes that dynamically share space on your disk rather than requiring fixed partition sizes. A management volume typically requires 30-50GB. Unlike older partition methods, this only uses the actual space needed for macOS system files (typically 30GB), not a fixed reserved amount.

For Apple Silicon Macs, additional steps are required before SoftRAID can load on the new volume. After installing macOS on the new volume, you must switch your startup disk back to your original system, then switch startup back to the new volume. This process signals macOS to reduce security restrictions, allowing third-party drivers like SoftRAID to load.

See the video below for step-by-step instructions.