This is a guest post by Vincent Clarke.
In this tutorial we’ll show you how to install Mac OS X Lion, OS X Snow Leopard, or OS X Leopard from a USB stick. In addition to these versions of OS X, you could also use this guide for installing older versions of Mac OS X from a flash drive. Officially, Apple launched OS X Lion back on July 20, 2011. Even with the release of OS X Mountain Lion due next month, people are still flocking to get the latest update of OS X on the App Store.
Apple’s OS X Lion relied heavily on improving overall system performance and speed while adding some cool new features to the GUI. Just like its predecessors, OS X Lion can also be manually installed from flash drives.
In order to get this done, you’ll have to first set up your flash drive with the proper installation files. These files can be found right on the OS X Lion DVD, (or if you downloaded it straight from the app store), on the InstallESD.DMG file on your computer. If you deleted this file after installing OS X Lion, you can try the Online Internet Recovery HD system by pressing Command+R or Command+Option+R when booting your Mac. From there, you can download the installation files again without a problem.
In addition to the installation files, you’ll just need a USB flash drive with at least 8GB of available memory. Once you have everything you need, plug your USB into one of your Mac’s available USB ports and follow these easy instructions to install OS X from a flash drive.
1. Launch your Disk Utility and then click on your USB drive. Make sure you don’t have any important data on the flash drive as you’ll be wiping it clean in the next step.
2. On the right, select the Erase tab and then set the Format to Mac OS Extended. Give your partition a name so that you can easily track and find where you saved your OS X installation USB. Once this is finished, select the Erase button.
3. Once the Disk Utility finishes wiping out any information or data on your USB stick and sets it as a new partition, you’re ready to add the OS X install files. Click on the Restore tab at the top and then drag the Lion source files or Lion DVD to the source field. Choose your newly partitioned flash drive as the destination file. Select Restore and then wait for it to upload. This could take anywhere from 10-30 minutes.
4. Once the restore finishes up, you should be able to launch your USB drive and see the OS X installation files there. When you try and select the OS X icon, you’ll get a pop up telling you that you can “install OS X from this volume”. Remove your USB drive safely and it should be good to go.
5. Next you’ll want to make sure you can install this on another computer. In this case, we’ll just check it on the same Mac. Plug in your OS X USB drive and then reboot your computer. When OS X is about to launch, make sure you’re holding down the Option key on your keyboard. You’ll see two volumes pop up from the installation menu. One will be your flash drive you just created. Click it.
6. The on screen instructions should guide you what to do next. In total, it took about 40 minutes to install OS X Lion on my Mac from a flash drive. Tell us in the comments below how long it took your computer.
7. After everything is finished, your Mac should automatically reboot using OS X Lion.
About the Author
Vincent Clarke is a blogger and copywriter for USB Memory Direct, a company that makes customizable flash drives for promotional marketing. He enjoys writing about the USB industry and the craziest flash drives that can be found on the internet.