how use WD SmartWare to set backup source = MyCloud & target = MyBook?
Smartware is used to backup computers (source) to the MyCloud (Target).
Safepoints are used to backup the MyCloud (source) to the MyBook (Target)
If you have WD SmartWare on your computer open it, click on the Help tab and then the Backup button and read the instructions.
You can find the information in the User Manual too. See Backing Up Files.