So let’s say you bought the cheapest plane ticket you could get, even though it involved a five hour layover in Shanghai, but it was only when you were heading out to the airport that you noticed the layover also involved switching airports in Shanghai! Fear not, this post is intended to help you make your connecting flight. When it happened to me I discovered that most of the relevant online information was out of date or confusing, so hopefully this will help others navigate their journey!
This post covers the trip from Shanghai Pudong International Airport 上海浦东国际机场 (上海浦東國際機場) to Shanghai Hongqiao International Airport 上海虹桥国际机场 (上海虹橋國際機場). I assume that it should help those going in the opposite direction as well, but I haven’t personally made that trip.
Arrival
When you arrive at Pudong the first thing you need to do is get your luggage and go through immigration. If you are arriving in China from a different city than your destination you may be eligible for a 144-hour visa-exemption. Check this site for more information. If you are lucky, someone is working at the separate counter set up for this and you can skip the big line. (It was closed when we arrived late at night going the other direction, but was open on the returning flight which arrived during the day.) Make sure to have a print out with your connecting flight information.
Maglev
After collecting your luggage (if any) and exiting customs, take the escalator to the right and head up to the second floor. There you will see a passage to terminal 2: 
At the end of the passage, turn left. If you see the subway entrance and a food court you’ve gone too far! 
At the end you will see a ticket booth just to the right of the Maglev entrance. The Maglev is called 上海磁浮示范运营线 (上海磁浮示範運營線) but usually abbreviated as 磁浮列車。 At the ticket booth you want to buy a combined Maglev & Metro Pass 磁浮地铁一票通 (磁浮地鐵一票通). It is ¥55 for a one-way ticket. 
You will have to have your luggage X-rayed on the way through to the Maglev train, but it is very quick and you don’t need to take out your laptop, etc. Once inside you can’t go down to the platform until the train arrives. 
The Maglev journey is about 8 min.
Subway Line 2
There is only one stop: Longyang Road Station 龙阳路站 (龍陽路站). Once you get out, just take the escalator down towards subway 上海地铁 (上海地鐵) line #2. 
At the bottom of the escalator you have to cross the street, and have your luggage X-rayed again. 
I couldn’t find a down-escalator, so I ended up having to carry my luggage down one flight of stairs. Not sure if there is an alternative? At the bottom take the side that is NOT going back to Pudong Airport! 
The Line 2 journey is about 50 min. Here’s a list of all the train stops.
Subway Line 10
Once at the Hongqiao airport exit you will probably have to transfer to a train that takes you to Terminal 1 (the exit is at Terminal 2), but check with your ticket. For this train, follow the signs for subway line 10, and take it one stop. (You can still use the same metro pass for this.) 
After getting out at Terminal one, there is a five minute walk under a covered walkway. 
Once in Terminal 1, the escalator to the check-in counters is straight ahead and to the left. 
Getting from Terminal 2 to Terminal 1 takes about 15 min.
Good luck! If anything is different from what is reported here, please leave a comment…
