I prefer keeping Lion on a USB keychain so that I can add files to the USB drive to customize the installation but if you’re just looking for a bootable copy to troubleshoot your hardware, feel free to go with the DVD option and save yourself a little cash. To do this, you will need a storage medium (DVD, flash drive, or hard-drive partition) of at least 4GB in size, and then just follow these steps: After choosing Show Package Contents on the.

(If you happen to own a Mac with a disc drive, consider creating a DVD backup of Lion. The app will give you the option of creating a bootable drive out of either a DVD or a USB keychain. Start the Lion DiscMaker app with your USB flash drive plugged in and with the Lion install file sitting inside your application folder.

Lion DiscMaker makes this part of the process a snap. You have been warned! Creating Your Bootable Drive Now, before you start formatting your drive, back up anything currently on your flash drive that you’d like to keep–because this process will completely erase the contents of the USB drive and rewrite it with a copy of Lion. Restore the InstallESD.dmg onto the HFS+ formatted USB (GUID). Downloading a third-party app just to handle this process is a bit of a bother, but Lion Discmaker enormously simplifies the process of installing Lion on a USB keychain. Open the package contents of the Lion installer from the Mac App store to get the InstallESD.dmg. Power on the system, or restart it if it’s already on, and immediately press and hold the Option key when it starts booting. Intel Macs Simply plug your created USB drive into an open USB port on your Mac. To streamline the process, download the free Lion DiscMaker app. There are two different methods to boot your Mac from a bootable USB, depending on which processor your Mac has. If you already own a copy of OS X Lion, you should be able to download a fresh copy at any time from the Purchases tab of the Mac App Store.

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