Beijing airport is fairly modern, with clearly marked signs to immigration and transfers. There are three terminals, although most international flights operate out of Terminal 2 and 3. There's a train that runs between the terminals, and once we cleared immigration we waited for the train to terminal 3C for our baggage.
Once you pick up your baggage you have to scan your passport again to get through to customs at the automated lanes - this can be a little bit tricky, and I did see some people getting held up because they couldn't scan the passports properly.
Security was as expected, a little bit more strict than some airports. Even going through the 'Nothing to declare' lane, you still have to scan your bags again.
There's a counter that sells local SIMs after the baggage area, although the other shops were closed by the time I arrived past midnight. For such a massive international airport, the shops do close by midnight and there are very few shops open if you arrive late night, so plan accordingly.
The signs to the exit and the different transportation options are clearly marked in English. The shuttle bus was still running late at 3am, but I decided to get a cab instead to save time.
Beware the taxi touts, they're waiting right outside the arrival hall. They even show you official looking cards marked 'Airport Taxi' which prices marked charging 580 yuan (RM375) for a city transfer, which drops down to 280 yuan (RM180) for a so-called 'nearby' transfer. Ignore them and follow the signs to the taxi area a floor below the arrival hall where there will be a row of taxis with some airport officials waiting. A taxi to the city centre at 2am cost me 130 yuan (RM80).