How to Create a Mac Recovery Disc
Items you will need
Snow Leopard installer DVD
External hard drive, additional internal hard drive or USB flash drive
Step 1: Choose the medium you want to use for your recovery disk. While Mac OS X 10.6 Snow Leopard allows you to repair your Mac's hard drive using disk utilities installed with your operating system and running from the drive you are trying to repair, this may not help you solve the full range of problems that can affect your system. Choose a second internal hard drive, external hard drive or removable USB flash memory device (minimum 8 GB capacity) for optimal flexibility.
Step 2: Make sure the drive you plan to use for your recovery disk is plugged in, powered up and ready to go. You should see its icon in the Finder's drive list.
Step 3: Place your Mac OS X Snow Leopard installer DVD in the optical media drive of your Mac. Once the Snow Leopard disc mounts to the desktop of your system, double-click on the Mac OS X installer icon to launch it.
Step 4: Set the target disk for your Snow Leopard installer to the drive you have decided to use for your recovery disk. Choose a minimum installation of Mac OS X Snow Leopard if you are installing to a removable flash drive. Click "Customize" to choose which operating system options to install.
Step 5: Apply any updates to the operating system on your recovery disk once your Snow Leopard installation is complete. If you already have downloaded updates to apply to your start-up drive, use those installers to update your recovery disk's OS installation. Download the updates from Apple's website if you do not have the necessary installers.
Step 6: Install any optional third-party disk-repair tools you wish to be able to run from your recovery disk. Such utilities may offer you capabilities beyond the repair and verification functions available in Snow Leopard's Disk Utility application.
Step 7: Boot your Mac from your recovery disk and run disk repair tools. Hold down the "Option" key as soon as your Mac starts up and wait for the start-up disk selection screen to come up on your monitor. Choose your recovery disk as the start-up drive instead of your regular boot drive.
Step 8: Run Apple's Disk Utility and any optional third-party tools you installed on your recovery disk. Restart your Mac from your regular boot drive when your repairs are complete.