How to set up a Mac to run either macOS Mojave or macOS Big Sur
Big Sur is a major upgrade to macOS, and some people are ready for it. However, if you’ve been running Mojave or an earlier version of macOS to keep 32-bit applications running, you may still be holding back. If you’re otherwise ready to move forward, you have a few options for keeping your Mojave installation active. In each case, I’d recommend starting by making a full disk image backup of your current macOS setup with Disk Utility, SuperDuper!, or Carbon Copy Cloner. In case something goes wrong, you can revert to it or restore from it. Your easiest path is to buy or use a sufficiently large external drive and clone to it directly from your current Mac. This lets you even boot from it in a pinch, so you don’t have a…