What is best way to travel from Beijing speed train station to Hilton hotel near Tinanmen Square?

Do you refer to the South Railway Station? If yes, the cab fare to Hilton Wangfujing Hotel is CNY 30-40 in the day time.
Or from the South Railway Station, you can take subway line 14 to Puhuangyu Station and line 5 to Dengshikou, Exit A. After arriving, walk southwest around 850 yards to find the hotel.
You can choose the way you like.