Hi,I wanted to go to imperial hot spring sauna in doumen

First, you need to take bus 31 to Mingzhu Shangye Guangchang; then, transfer to bus K4 to Yu Wenquan (Imperial Hot Spring) directly. It takes about 1h 50 minutes and costs CNY 7.

thank you William for the answer very kind of you
by the way,I just get back from hot spring sauna, it took me 3 hours to get there yesterday but it's all worth it, really enjoyed staying there,Amazing places. definitely comeback again next time.
I ride bus no.601 from gongbei port terminal and get off at (E YU DAO)terminal and transfer bus no.609 or k4 going to hot spring sauna (last station ).

But I think is way easier if you booked online,there's a shuttle bus pick you up in gongbei port terminal to the imperial hot springs (only 70 minutes ),the packaged is already included (hotel room,breakfast, hot springs, massages, fireworks and bus shuttles going way back to gongbei port terminal )which is way more cheaper than if you going straight to the hotel like I did (luckily I still got room left) and the prices not included massages and buffett dinner at the village street Foods(my hotel room RMB1050,full body massage RMB 198,buffet dinner RMB168).just share my experiences, i think booked online and earlier before is way more cheaper and convenient.