Sometimes it is not easy, but we have found a really good application that will help you keep them updated and safe.
Puresync includes many interesting features and it is not difficult to use.
You choose the folders and files you want to backup and the destination drive. From then on, the program will check it and each time you modify the original file PureSync will backup it automatically.
You can plan backups to be done everyday, everyweek,... or automaticcally when files are modified.
Now you may think it is not important but in case of crash you'll welcome having used it.