Hi, What is the best way to get from Chengdu to Dujiangyan volunteer panda base?

Oh, you can take bullet train from Main Railway Station and get to Qingchengshan Railway Station. Then take a taxi to the base directly. Or you can take long-distance bus at Chadianzi Bus Station and arrive at Dujiangyan Bus Station. After arriving, take a taxi to the destination.
Choose the way you like. :)