Create a bootable USB dirve for an existing WinPE wim file

I use this procedure to create a bootable USB disk for a WinPE image I use at work for setting up physical machines.

1. Follow the steps on Technet to create the folder structure required;
   Create a Bootable Windows PE RAM Disk on a USB Flash Disk
2. Copy your wim file into the \Boot\Sources folder and rename it to boot.wim.

Although the Technet link is for Windows 7 or Windows Server 2008 R2, it works fine with the Windows 8 ADK.