How to downgrade from OS X El Capitan back to OS X Yosemite

[iMore.com]

The OS X El Capitan public beta is a way to test the next generation of Mac software. If it turns out you don't enjoy the process, or would prefer to wait and try again later, you can go back to Yosemite. Downgrading is a simple process, but it's also a bit of a chore. Don't worry, though, we'll walk you through it!

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