Take metro line 2 and transfer at Xizhimen station, Exit A to Beijing North Railway Station, go upstairs to buy ticket. I bought the ticket for 09:03 at the price of 6rmb and less than one and a half hour later, I arrived at Badaling.

Just follow passengers to walk like 600meters and you will at the entrance.

I bought the 60rmb cable for getting up and a 45rmb ticket for walking like 30minutes down to the bear exhibition place. Never buy double cable ticket as no one wants to go back to the same way.

I took the ticket back to Beijing leaving at 1pm still at the Badaling station and also still 6rmb. It is a little hard even for a Chinese to get back to the station as you walk down to the different entrance. You can ask if you can speak Chinese,if not, keep an eye on the billboard for direction on the ground.

The train is absolutely the best public transportation to the wall and on the way you can see a museum for an engineer and Qinglongqiao station which can be seen in a movie.

If you want to see the train please click below:

http://www.douban.com/note/187612074/