Undo a clone and revert back to WD Smartware

I made the mistake and used Acronis True Image to clone my c: drive. It did so successfully but it also used my entire 1tb WD My Book Essential hard drive. I want to undo the clone and use WD Smartware instead to just do backups of my files. How do I do this?

Personally I would be to zero out the drive using Data Lifeguard diagnostics than re-partition and re-format the drive.

Once formatted, it should show up in smartware (as long as its supports the drive) or the third-party backup utility of your choosing.