Sublime will automatically back up all of your repositories on a schedule you create. Backups can be stored locally on the same server, or on a remote file share. For obvious reasons, a remote file share is recommended.
Each time a backup is performed, an event is written to the Windows event log. This captures the time required for the backup, the number of repositories backed up, and how many errors occurred. It is recommended that you review this information on a regular basis to ensure backups are happening successfully.
Backups are configured using the Backups screen in the administration section. The Backup Path setting is the full path to where backups will be stored. Network paths can be provided using a typical UNC path such as \\mynas\backups.
The Schedule section lets you specify the time of day and days of the week that backups should be performed.

The Backup Account section allows you to specify the user account that will be used to copy the backup files to the backup location. Enter the username and password for a user that has full read and write access to the path entered as your Backup Path.

At this time, only full backups are supported and each backup overwrites the previous backup. If you require a more sophisticated backup scheme, you can use Sublime to create a safe backup every night, and then use a file system backup utility to create a backup of your backups. This might sound like an odd setup, but simply basking up the file system when repositories are in use may result in lost data or corruption. Thus the safest approach is to back up the backed-up repositories after Sublime has finished its backup.