Here’s an affiliate link to a 16GB USB drive that comes already properly formatted for the purpose of installing Mac OS X: It’s a good place to buy Mac friendly stuff. If you don’t already have a USB flash drive, or want a USB flash drive that is already compatible with Mac OS X then you can purchase one from the MacMall. The USB Flash drive will then start to format in most cases it takes less than a minute. Then simply press the “Erase…” button on the bottom right when done. It would probably would be best however to make it something recognizable like “Mac Install” or “Mountain Lion Installer”. Under the selection for “Format:” select “ Mac OS Extended (Journaled)“, and name it anything you’d like. Select the USB drive that is to be formatted, then select the Erase tab.
We’re going to format the USB drive, so make sure there isn’t anything on it that you need, as formatting will erase everything on the USB drive. Plug it into your Mac, and launch Disk Utility (located in Applications/Utilities). Nowadays USB Flash drive are really cheap and can be purchased at almost any electronics store (the Flash drive I use is 16GB and only cost $15).
To create the bootable disk image, your UBS drive has to have at least 8GB of storage.
