How to Make a Bootable OS X Mountain Lion USB Drive or SD Card Installer

Posted on July 26, 2012 by

Apple has released OS X 10.8 Mountain Lion in the Mac App Store, but some of you may be interested in installing it from a USB drive, SD card or DVD. Lion DiskMaker has been updated with support for Mountain Lion, just follow the steps below to create your bootable media.

You will need one of the fallowing:

  • SuperDrive and a writable DVD (dual-Layer, 8,5 DVD-R)
  • 8GB (minimum) USB flash drive
  • 8GB (minimum) SD Card

Step 1: Download Mountain Lion from the Mac App Store.

Step 2: Download the latest version of Lion DiskMaker (current version is 2.0rc2).

Step 3: Open the compressed file and run the DiskMaker app.

Step 4: Choose the correct version of OS X, “Mountain Lion (10.8).”

If the utility doesn’t find the image, go to the Applications folder and find the copy of Mountain Lion you downloaded and follow these steps:

  • Right click on the downloaded file and select “Show Package Contents”.
  • Go to “Contents” and open the “SharedSupport” folder and you will find a file titled “InstallESD.dmg”.

Step 5: Lion DiskMaker will give you two options – “Burn a DVD” or “Create a boot disk.” Select “Create a boot disk.”

Step 6: Ensure that your 8GB or greater USB drive or SD card is mounted. Choose partition and proceed.

Let us know if you have any questions. You can find out more information on Lion DiskMaker here.