in order to edit a .conf file you have to type this in the console as root.

vi /etc/lilo.conf

then scroll the the spot where you want to add something. then hit "i" on your keyboard to insert. after you are done typing hit "esc" and then type this without the quotes ":wq!". Then your added string should still be in the configuration.

Make sure to follow the directions by running Lilo after changing the config.

Hope this helps!