how to do a unattended installation

Hi,
I am attempting to do a unattendd installation of NT 4 workstation but am having dificulty.
It needs to be done from a floppy disk and using the CD ROM not the network.
I haven’t been able to get a great deal of information about how to do unattended install.
I have found plenty of info on what it is but not “how to do it”. I also want to be able to install a service pack update at the same time.
Any help would be great thanks.
PS I have tried to use the Setup Manager on the NT 4 CD, but when it finishes the answer file it keeps coming up with an error when I try to save it in a folder on the C: drive.