Hey guys this is a tutorial on how to set up a Windows to Go (a live Windows 8 boot) USB using any version of Windows provided you have a copy of Windows 8, Windows 8.1 or Windows 10 Technical Preview.
Things you will need:
A USB or external HDD with 8GB of space (You will only have around 2.4GB free)
A copy of a Windows 8, Windows 8.1 or Windows 10 Technical Preview (Any version is fine including upgrade ones). The 90 day evaluation copies from the Microsoft website even work.
Just over an hour of your time depending on your hardware (mine took 88 minutes, 11 seconds)
Instructions:
Locate your Windows ISO and mount it (if using installation disc, insert that)
Navigate to \sources and copy the install.wim file to your desktop
Insert your USB or HDD and format the partition as NTFS with the default allocation
Download GImageX from Softpedia and extract it (Download GImageX (Windows, 32/64bit)
Run the x86 or x64 version depending on the version of Windows you are using
Navigate to the "Apply" tab
In the source section enter or browse for the location of the install.wim we copied earlier
In the destination section enter or browse for the location of the device you want to use for Windows to Go
Leave the checkboxes unchecked and hit apply
Navigate to your Windows to Go disk and go to \Windows\System32
Open up CMD from this location (or change directory to the above folder) and enter
bcdboot.exe X:\Windows /s X: /f ALL
Replace "X:\" with your Windows to Go drive letter
Congratulations! Your Windows to Go device is now ready and all you will have to do is boot from the USB at startup then run through the one time configuration settings!
If you have any problem feel free to comment below and I'll try and get back to you!

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic