I'm planning a trip to the Guangzhou famous shopping centre called
"Shangxia Jiu Pedestrian Street". I'll be traveling either from
Hong Kong or from Shenzhen whichever is cheaper. Can you please
advise the cheapest way to get there, and how? I understand if I
travel from Shenzhen, I should take the train from Lo Wu Train Station
to Guangzhou, then I don’t know how to get to the "Shangxia Jiu Pedestrian Street".

Can you please advise in details? Thanks very much!