I will be staying at Haizhu Area in Guangzhou and intend to go to Shenzhen Dongmen area .

I suggest you take a bullet train from the central rail station to Shenzhen Luohu Station. If you refer to Dongmen Pedestrian Street, take a taxi then to that area at a cost of CNY10. Or at Luohu metro station, take Luobao line to Laojie station. Take exit A and walk to Dongmen.