Without users a low tech and easy strategy is simply to back up your course every few days and download to your home computer. There are suggestions here for easy manual backups.
Once you have students on your system, you have the responsibility to keep their work safe. I think automatic scheduled backups are a must.
Like almost everything in Moodle, you can pay to have someone set this up for you. For myself, I like to solve problems and i am using Dropbox's free 2GB of space and a simple script to transfer backups at midnight for a reliable and cost free backup strategy. The script is here.