The integrated circuit card (ICC card) that can store credit for multiple rides, also called the Yikatong, It need to pay RMB 20 deposit, plus whatever amount you want to put on the card.

After buying your ticket you then proceed down the stairs to the platforms. all lines now collect fares through automatic fare collection machines that accept single-ride tickets, move your ticket close to the sensor of the electronic barriers, the automatic gate will open and proceed through the barriers.

Signs on either side of the tracks tell you the upcoming stations,
so have a look to see which side you need to join the train on.

Subway upgraded signal equipment to increase the frequency of trains and added to the capacity of subway trains. The minimum wait-time has been reduced to 2.5 min. It is generally closed after midnight, unless a special occasion prompts extended operating hours. The first trains depart terminals at around 5 am and the last leaves at around 11 pm. 　　　　Beijing Subway Lines

After get on the train, You might see the signs which show the next stations, you could
count your stops to get off or transfer. announcements are in Chinese and English.

The signs of next station

The signs of transfer line

The signs of exit or transfer

The Exit of Subway Station