First thing you need to do is download the deployment kit.
It can be downloaded here.
After installing it you need to insert the Windows 7 CD/media. This can be done with any operating system but you need to have the media for each specific OS.
Open the CD and inside the Sources directory there will be a file called Install.wim. Copy that to a location that you will remember.
Open Windows System Image Manager
Then select File -> Select Windows Image -> Navigate to where you saved the Install.wim -> click Select.
It will say that you don't have a catalog. That's fine, just click Yes and it'll create one for you.
After it completes, select File -> New Answer File.
Now we are ready to start building the Answer file.
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