Dial the International Dial out code of your country (eg: from UK - 00)
00 + 86 + City Area Code + Local number
If you need to make a call from China you will need dial 00 (eg: 00 44 for UK) and from Hong Kong 001.
For Australians the international code is 0011 etc etc.
If ringing a Chinese mobile you DON'T put in the code for Nanning. IE: 0011 86 then the mobile number only.

Beijing 10
Changchun 431
Changfeng 551
Changle 591
Chengdu 28
Chongqing 23
Conghua 20
Dalian 411
Da-tong 971
Fanyu 20
Fumin 871
Fuzhou 591
Guangzhou 20
Guangzhou 20
Guiyang 851
Haikou City 898
Hailar 470
Handan 310
Harbin 451
Helan 951
Hong Kong 852
Huaxian 20
Jiangmen 750
Kaihua 570
Kaiyuan 410
Kelamayi 990
Lhasa 891
Lintong 29
Nanjing 25
Nanning 771
Nantong 513
Peilin 810
Qingdao 532
Shanghai 21
Shangqiu 370
Shenyang 24
Shenzen 755
Taiyuan 351
Tianjin 22
Tianjin 22
Wenzhou 577
Wuhan 27
Wuxi 510
Xiamen 592
Xi’an 29
Xiangfan 710
Xianyang 910
Xinmin 24
Yangpu 890
Yueyang 730
Zhicheng 27