You should memorize your password or write it down somewhere where it is safe. You will have captured all the arcane numbers that must be entered in the control panel to enable you to get online. Now your documents and the screen shots to external storage. You have to decide just what kind of external storage. If your computer contains a floppy drive, you might be tempted to try to backup to floppy disks.
Floppies are the worst possible storage medium for important files.
Just say no. A better medium is a ZIP or JAZ disk. Either method requires the investment in an external drive. Blank CDs, which store 650MB of data, can be had for as little as 80 cents apiece in quantities of 50, and as little as 43 cents in 100 packs. Certainly, CDs provide the most inexpensive form of backup storage you can find.