You can schedule a backup of the database. If ManicTime was not running at the time the backup should be created, it will create one next time it is started. You can use "Backup now" button to test the settings.
Choosing which data to backupManicTime uses two databases, ManicTimeCore and ManicTimeReports. ManicTimeCore contains all the data you need to restore and it can be very small. ManicTimeCore is about 1/10th of the size of ManicTimeReports.