Log into backend Admin and navigate to Components -> Akeeba Backup for Joomla -> Control Panel
Click the Default Backup Profile button to initiate the backup process
Wait until the process is complete and then return to Control Panel.
Download Backup file
You can download the backup file by FTP, if you have an FTP program, or from within Akeeba.
Click the Manage Backups button
Click the Download button next to the backup you want to download. Only the three latest backups will be available, by default Akeeba is set to keep only three and delete earlier ones.
You'll get a warning from Akeeba recommending to use FTP. Ignore this, if you could you would, otherwise...
The file will be downloaded to your Downloads folder on your device.