Here is step by step tutorial with images that explains how to create bootable windows 8 USB Drive . Windows 8 was released recently for anyone and everyone to try out. It isn’t the complete version of Windows 8, but provides a nice glimpse at the future of Microsoft’s desktop operating system. You can download Windows 8 Consumer Preview from this LINK
1) Download Windows 7 USB/DVD Download Tool from this LINK and install it .
2) Launch the Windows 7 USB DVD Download Tool. Click on Browse button and double click to choose Windows 8 ISO installation file.
4)Before you click erase USB device, again make sure you backed up all the data on your USB key .
Click on Erase USB device and click Yes
5) Wait for the Windows 7 USB/DVD Download Tool to go through the procedure.
And that is all!