Windows Assesment and Deployment Kit (ADK)
For the next step you will need the Windows Assesment and Deployment Kit (ADK) for Windows 8, which you can download and install from Microsoft's Technet website. For this Windows 8 installation you need the Deployment tools, which give you access to the program OSCDIMG. It allows you to create a Windows 8 installation file.
After installing the ADK, you can via the Start Menu start up ‘Deployment and Imaging Tools’. It will send you do the command prompt, and here you can run OSCDIMG.