Train and coach bus both can take you to get to Huludao. You can take the Train No.K715, K369 or K7349 to go to Huludao from Dalian railway station. It takes more than six hours to get there by train. There are five coach bus stations in Dalian downtown. You can go to the Jianshejie Bus Station to find a coach bus to go to Huludao. Please refer to https://www.travelchinaguide.com/cityguides/liaoning/dalian/getting-there.htm for the details of Dalian long-distance bus stations and railway station.

Hi, besides of the Jianshejie Bus Station, you could also take the Huyue Express Bus from Dalian to Huludao. The bus station is at the Changjiang Road (north side of the Victory Square)
There are three coaches departing to Huludao, respectively at 08:00, 13:30 and 16:30. It takes 5 hours on the way and costs 107.5yuan per person.