How do I get from Beijing South Station to the wall and how long does this take?

Is it the first time you have been to the wall? If so, I suggest you visit Badaling section. You can take subway line 4 from the south railway station to Xuanwumen Station. There you can change subway line 2 to Jishuitan Station. Then get out from Exit A and walk a few minutes to Deshengmen Arrow Tower. There you can take bus no. 877 to reach the wall. Please get there before the noon to ensure that you can catch the bus.