Microsoft announced the availability of the Windows 8 Consumer preview overnight in Barcelona. If you want to try it on one of your computers, you can download the ISO file from Microsoft's Web site. You then have the option of either burning that ISO file to a DVD or creating bootable USB key. We are going to focus on the latter option in this article, because it makes installation so much easier, especially considering many systems don't come with an optical drive these days.
Step 1: The first thing you'll need is a USB key that is 8GB in size or larger. USB keys that are 4GB may not work unless you install the 32-bit version of Windows 8.
Step 2: Download the version of Windows 8 that you desire (32-bit or 64-bit). Keep this product key on hand as you will need it later during the operating system's installation: DNJXJ-7XBW8-2378T-X22TX-BKG7J.
Step 3: Download the free version of UltraISO from here, as this will be needed to transfer the ISO's contents to the USB key and make it bootable. Install UltraISO and run it as an Administrator.
Step 4: Click on the second icon from the left to open the ISO image. The contents of the image will now be shown in the window.
Step 5: From the menu at the top, click Botable and select 'Write Disk Image'. The next scene should auto-select the 'USB+HDD' option, make sure your USB key is selected and click 'Write'.
The amount of time it will take to copy the data and make the bootable USB key will vary; ours took about 15min. You can then install Windows 8 Consumer Preview on any machine that supports booting from a USB key. Only install the preview on a machine that is spare because you will not be able to uninstall Windows 8; and make sure you back up your data if you'll be installing on a machine that already has things on it.