How do you add files to a backup CD?

[Rust1]

I have no probs making backups but I would like to know how to add files ie., patches and/or updates to a backup? I would like to be able to add for example the bonus pak for UT so I don't have to hunt them down and download them over and over everytime I restore my HD. I can make backup cds on separate cds but would like to keep them on the game cds whenever possible. I currently have a Plextor 12/10/32 CDRW, Fireburner Ver1.03/1.06, BlindRead 3, Adaptec EasyCD Creator (yeah I know not too many people like the last one but I use it for Direct CD and SpinDoctor. lol)
Thanks in advance for any and all help.