The best way is bus. Hangzhou West Bus Station has buses to both Tunxi and Huangshan Scenic area. There is no train from Hangzhou to Huangshan, by the way.

Ms.Cindy
Are there many timings of the buses going to Huangshan from Hangzhou West Bus station? Do I need to book the bus-tickets in advance? Thank you.

If　you can get to Hangzhou earlier, you can get to the bus station to buy earliest bus to Huangshan. There are many buses a day, usually not necessary to book in advance. Tell the ticket officer that you are going to Huangshan Scenic Area (Tangkou). If you take the afternoon bus (after 15:10), you can only get to Tunxi or Huangshan district first, then stay one night there. Get to the mountain the next day.