Apple has set free OS X Lion and is available on th Mac App Store. The only way to upgrade to Mac OS X Lion is by downloading it from the Mac App Store. Thus to install Mac OS X lion on your Macs you have to download it on each Mac. This issue can be solved by
* Making a Bootable DVD Disc
* Making a Bootable USB Flash Drive
In this tutorial, we will see how to make a Bootable Mac OS X Lion Flash Drive. The steps are as follows:
How to Make Mac OS X Lion Bootable Flash Drive:
Step 1: Download Mac OS X Lion from the Mac App Store.
Step 2: After download is complete, right-click on the file and select “Show Package Contents”.
Step 3: Now, go to “Contents” and Navigate “Shared Support” Folder. Find for the file named “InstallESD.dmg”. Copy this to the desktop.
Step 4: Plug-in a USB Flash Drive to your Mac. The storage capacity of the Flash Drive should be atleast 4GB. But 8GB Flash Drive is suggestable.
Step 5: Now open the “Disk Utility” and drag “InstallESD.dmg” from the desktop to the left hand sidebar. Now,select the attached USB from left side and click on “Partition” tab.
Step 6: Select “1 Partition” from the Volume Scheme dropdown menu. Choose “Mac OS Extended ” from the left.
Step 7: Now, click on “Option” and select “GUID Partition Table” and press OK. Now click on apply to start formatting. Once the drive has been formatted, click on “Restore”.
Step 8: Now, choose USB Drive as the destination and InstallESD.dmg as the source. Click on Restore. This will create the Bootable Lion USB Flash Drive.
Step 9: Reboot your mac with the USB Drive plugged in. Hold the “Option” key on your keyboard when you hear the iconic OS X startup chime. You can now boot into your Flash drive from there. Now, follow the on-screen instructions to install Lion on your Macs.