Sorry, but again I'm going to need more detail. Are you referring to:
http://www.howtoforge.org/perfect-se...ntu8.04-lts-p7
If so, I don't see any explicit instructions to edit anything. However, whatever you're trying to edit, the answer is fairly generic. If you're at a command line/text-only interface, open nano using this command:
nano file.txt
(Where file.txt is the file you want to edit). nano operates the same way as notepad in Windows; when you're done editing the file, press ctrl+x which will prompt you to save, then close the program. If you're in a graphical interface where you can use a mouse, gedit is probably your best option; on most systems this will be under Accessories->gEdit text editor. It operates exactly like notepad in Windows.