Marco Polo Kowloon to China Hotel Guangzhou.....

If you mean the China Hotel, A Marriott Hotel, Guangzhou,122 Liu Hua Road, Yue Xiu District, you can walk about 700m to Haiphong Road, Tsim Sha Tsui to take bus line 81C to Burley Shopping Avenue Station and then walk about 1 km to Central HK Ferry Terminal to take a ferry to Nansha Port. Get off the ferry and take the metro line 4 from Nansha Port Station to Chebei Nan Station and transfer here to metro line 5 to GZ Railway Staion. Walk to north about 1.5km you can get there.

It takes about 7 hours and around CNY 250.