Hi, Kim,
There are several ways, depending on what CD hardware and software you have.
The CD drive should have come with some software, and you can buy other,
more capable software.
The easiest to use (although some people feel it's still a bit flaky) is
"packet writing" software that essentially makes the CD look like a big
floppy disk. The most popular of these are InCD from Nero, and DirectCD from
Roxio. [If you use CD-R (write-once) disks and you erase or overwrite a
file, it can't really delete or rewrite the data, so it just marks the old
copy as unreadable. If you use CD-RW disks, the data can actually be deleted
or rewritten.]
The other common way is to save the document file to the hard drive, and
then use CD-burning software (e.g., Nero Burning ROM and Roxio Easy CD
Creator) to copy it from there to the CD. This is more reliable than packet
writing. If you use "track at once" recording, you'll be able to add more
files to the disk later; "disk at once" recording closes the disk and won't
let you write to it again.