Where could we ride bus no. 6 to Banshengdong Wharf or no. 21 to Zhujiajian Wugongzhu Wharf?

Hi, I'm Frances from Philippines. We would like to go to Mt. Putuo by last week of June. Please provide us detailed directions on where and how could we go to Mt. Putuo from Shanghai because directions above is not that cleared and detailed for visitor like me. Thank you. Hope for immediate response.