With OS X 10.7, a.k.a. Lion, Apple stopped shipping physical copies of its operating system and instead opted for electronic delivery via its then-brand-new App Store. For the first time you could update your current configuration to the latest Apple OS with just a couple of clicks, a few restarts, and about 90 minutes of waiting.
Performing a clean installation, on the other hand, was a bit problematic. Lion also introduced a new recovery partition, and if you wanted to perform a clean installation, you had to run through a lengthy process of first installing it over Snow Leopard, rebooting into the recovery partition after the upgrade had completed, and then whipping over to your boot drive and installing the new OS on top of the now-clean boot drive. This was a pain in the tush because you had to install the OS twice: once to create the recovery partition and again to put the clean OS on the drive.
BYTE figured out a way to bypass this extra installation and wrote it up in How To Create an OS X Lion Install Disc. However, even this workaround was a bit involved for most people.
In this updated how-to, we've got a simple way for you to create not only a boot disc for Mountain Lion but Lion as well. The key is a handy app called Lion Disk Maker. The app uses Apple Script with a very nice GUI in front of everything.
To begin, download Lion Disk Maker. It comes in the form of a zip file. Unzip it and move it to your Applications\Utilities folder.