We will be arriving by train to Shanghai Hongqiao; our hotel is Holiday Inn Express Zhabei; SH

There is about 21km between.
it is suggested to take the subway line 2 to Zhongshan Park Station and then change to line 4 to SH Railway Station. Get out of the station from Exit 4 and then walk to your hotel.
If you cannot find the direction, it is suggested to ask the local people.