Backing up is VITAL. What would you do if your computer crashed and you lost all your data or your practice burnt down?
What I do:
1. Time machine backup which backs up new data every hour
2. Full copy of my whole computer at least once a week (I use SuperDuper) and rotate at least 3 Hard Drives
3. Daily copy onto a USB drive of important data (especially EzyPAASS)
4. Take 2 & 3 off site
N.B. To backup EzyPAASS you need to copy the whole EzyPAASS folder onto your e.g. USB drive