1. Login to WHM.
2. Click on Configure Backup.
3. Click on Enabled check box for Backup Status.
4. Specify backup related configuration like below:
Backup Retention Daily Weekly Monthly
Days to Run Backup
Incremental Backup (only backup what has changed.)
FTP Backup Directory (optional, a directory called cpbackup in the FTP account's directory root will be used if none specified)
examples: /backup/, /backup/cpbackup
FTP Backup Passive Mode (required if you are behind a firewall or FTP backups fail)
5. click on Save button.