Possible Duplicate:
How to install Windows 8 from USB flash drive?
How do I make a bootable USB with Windows 8? I would like to install it on my device with a broken DVD device. Has anyone faced this situation?
Possible Duplicate:
How to install Windows 8 from USB flash drive?
How do I make a bootable USB with Windows 8? I would like to install it on my device with a broken DVD device. Has anyone faced this situation?
Microsoft USB/DVD tool is very easy to use, you need 4GB flash drive and original untouched ISO image. You can obtain them for now from MSDN, Technet and some other places, just make sure to check the SHA of the ISO file.
Also you can use Universal USB Installer 100% free and support all of operating systems. Here is User Guide Link
If you do not want to the USB tools (or can't use them because your removable drive shows up as a local disk) it is possible to make a bootable USB drive with only the Windows 8 ISO and a working Windows machine.
cmd into the search field or click run > cmd | Right-click cmd and select Run as Administrator -- Vista or 7 only)diskpart and then list disk; locate your USB drive hereselect disk ? (? Is the number of your drive found from list disk )cleancreate partition primaryselect partition 1activeformat fs=ntfs quickexitcd followed by the directory of extracted ISO files OR just type in the letter of the drive where your ISO is mounted (i.e cd C:\Users\me\Downloads\Win8 or g:)cd bootbootsect /nt60 ?: Where ? is the letter of your USB drive. If you get an error about the wrong architecture you need to find the 32bit bootsect.exe (you can even use the 32bit Windows 7 file) program to run this command.The Microsoft USB/DVD tool does not work on some systems. So I used the following tool to create a bootable Windows 8 USB drive. This tool can be used to create only bootable USB drives, not a DVD.
Download Win8USB - Windows 8 USB Installer Maker.
Here are some screenshots

