How to Create a Bootable USB Drive With OS X Snow Leopard

Even though OS X Snow Leopard has been around for quite a few years, it remains a favorite for some Mac users with legacy software support. Additionally, some older Macs stopped receiving updates after Snow Leopard, forcing IT departments to continue support.

Because of this, it's important to keep a bootable Snow Leopard install disk around if you have a Snow Leopard machine or manage them. However, there is no automatic way to create this drive on your Mac, so I'll show you how to do so in this tutorial.

Note: Before starting this tutorial, ensure that you have a USB drive with at least 8GB of storage as well as a Snow Leopard retail DVD or disk image. Grey DVDs that were included with a Mac at the time of purchase cannot be used to make USB boot drives as they do not include drivers for Macs other than the computer it was shipped with.

Creating a Snow Leopard USB Boot Drive Using Disk Utility

Start by launching Disk Utility on the Mac. To do this, you can either search for the application in Spotlight or find it in the Applications folder. Locate the USB drive on the left-hand side of the window and click on its name, not its partition.

Partitioning and restoring your USB drive — Partitioning and restoring the USB drive.

Format the USB drive

Click the Partition tab
Under the Partition Layout header click on the 1 Partition option in the drop-down menu
Click the Format drop-down menu and select Mac OS Extended (Journaled).

Bear in mind that this will erase all data from the USB drive, so backup any important files before proceeding.

To format the USB drive drive, click the Apply button in the lower right-hand corner of the Disk Utility window.

Snow Leopard DVD or Disk Image

Locate a Snow Leopard disk image or DVD on the Mac
If you're using a disk image, mount it to the desktop
In the Disk Utility window, click the Restore tab in the USB drive's menu

Restoring the Mac OS X install DVD to your USB drive — Restoring the Mac OS X install DVD to the USB drive.

In the center of the window you'll see two boxes: one labeled Source and another Destination.

Drag-and-drop the USB drive's partition into the Destination box
Drag-and-drop the Mac OS X Install Drive disk into the Source box
At the bottom right-hand corner of the screen and click the Restore button

Disk Utility will restore the OS X Install DVD or disk image to the USB drive; this process may take anywhere from 20 minutes to an hour depending on how quick the Mac is.

Using The Snow Leopard USB Drive

Now that you've created a Snow Leopard USB drive, let's use it to install OS X Snow Leopard as well as access Terminal, Disk Utility, and other OS X utilities.

Power down the Mac and reboot while holding the Option key
Select the OS X Install DVD from the boot menu using the arrow keys on the Mac's keyboard
Select the language you'd like to use when prompted

Installing OS X Snow Leopard

To install OS X Snow Leopard from the USB drive, you'll need to reformat the Mac's hard drive. To do this, look towards the top of the screen and click on Utilities from the top menu and then click Disk Utility from the drop-down menu.

Formatting The Mac's Hard Drive

Click on the Mac's hard drive name
Click the Erase tab
Select Mac OS Extended (Journaled) from the Format drop-down menu
Name the drive whatever you'd like

Please note that all data on the Mac's hard drive will be erased, so backup all important files before proceeding.

Press the Erase button to format the Mac's hard drive

Starting The Snow Leopard Installer

Quit Disk Utility by pressing Command-Q on the keyboard
Press the Continue button
From the center of the window, select the Mac's hard drive
Press the Install button

OS X Snow Leopard may take a bit of time to install depending on the Mac's hardware. Upon completion, the Mac will restart and prompt you to create an account.

Disk Utilities on the Snow Leopard USB Drive

Additionally, you can access Disk Utility, Terminal, Safari (to access Apple help articles. not general browsing) and other Mac utilities from the Snow Leopard USB drive.

Boot the Mac to the USB drive using the steps shown above and click on the Utilities button from the top bar. You can access all available utilities from this drop-down menu.

It's nice to have these utilities available to use from the USB drive, especially Disk Utility. For example, if you believe your hard drive has died or is corrupted, you can boot your Mac from the USB drive and use Disk Utility to check the the hard drive's SMART status and repair said drive.

OS X Snow Leopard USB Drive, Completed

In this tutorial, I've shown you how to create a bootable OS X 10.6 Snow Leopard USB drive. You can now use the USB drive to upgrade, maintain and restore Macs to OS X 10.6.