There are loads of threads on punting in China. Use 'advanced search' and look on this forum only. The short of it is, it is hard work, and it can change between one month and the next due to local police. Hong Kong and Macau are way better. If you have no local Mandarin or Cantonese speaking guide, best bet is to find a glossy hotel-looking massage parlour and have a nice massage with happy ending.