How do we get to the Wong Tai Sin temple from harbour plaza Kowloon please?

May I know whether you are referring to Harbour Grand Plaza at 20 Tak Fung Street, Kowloon? If so, you can walk from the hotel to HUNG HOM FERRY BUS TERMINUS to take bus no. 3B to CHI LIN NUNNERY. Then walk to Diamond Hill MTR Station to catch Kwun Tong line to Wong Tai Sin station, whose exit B3 is very close to the temple.