Follow the IBM Informix system adminsitration course (Windows version)
Create yourself a backup strategy (when full, cumulative, incremental, how much downtime allowed, how much data loss allowed, what is the budget ).
Read the
-IBM Informix Backup and Restore Guide 9.4
-IBM INformix Storage Manager Adminsitrator's Guide 9.4
you can find them on
http://www-306.ibm.com/software/data...ry/ids_94.html
Start writing backup scripts
Start writing restore scripts
Test them
Implement them