Really short post:-)
To get a offline installation of Windows Assessment and Deployment Kit (formerly known as WAIK) download the Websetup ADKSetup.exe and start it – Windows .NET 4 is requiered. If not installed ADKSetup starts the installation – at the first screen you can set the location. When you specify a download path the complete ADK is stored this folder.
Importent: Start adksetup with Administrator permissions, otherwise the option “Download the Assentment…” is invisible.
Share the folder and execute ADKsetup.exe from this location.