Use lots of subdirectories and use compression where possible. Excellent compression programs in combination with tar are gzip and bzip2 . Now that you collected all your data, you may want to check whether it will fit on one CD or not. CDs will accommodate roughly 650MB, sometimes a bit more, but do not count on that, or you might end up with a coaster. Next, all your data has to be formatted into the ISO9660 fileformat that all CD-ROMs are are formatted in.
Little variations are possible.
Here is a list of parameters you might wish to use. You can combine most of them without any problems. Again, mind that doing it like this will only work for single-session CDs. When you are logged in through telnet, be careful anyway. Needed when we read the ISO-image from a harddisk partition.