|Tip 140||Create an Install and Recovery Stick|
Recent versions of OS X have been sold primarily through direct download from Apple via the App Store as an upgrade to the version of OS X already installed on your system. The installer is downloaded as an installation package and added to the Applications list.
This creates a problem if your computer is somehow made unbootable: how do you reinstall OS X now that your applications list is inaccessible? Alternatively, what if you simply want to create a clean installation of OS X?
The answer is to create an install and recovery USB stick. To do so, you’ll need a USB stick 8GB or larger, and you’ll have to wipe it clean as part of the process so it can be used only for the purpose of recovery and reinstallation. ...