Prague > Dubai > Shanghai > Singapore > Dubai > Prague

Your itinerary is definitely eligible for 144 hour visa free transit in Shanghai area.

You will print out your flight tickets with visible long flight number (14 digit). All you need to do is to declare at check-in in Prague that you will travel to Singapore via Shanghai using 144 hour visa free transit and you will repeat the same in Dubai when asked about it. You do not need any reserved seat or anything else. You just need your confirmed ticket. You will also print out your accommodation booking confirmation for at least for the first overnight in Shanghai.

Upon arrival in Shanghai, you will just approach 144 hour visa free transit counter where you will fill out a blue form. Shortly after, you will receive a sticker in your passport and will be allowed to exit the airport. You do not need to make any announcements to Emirates or CEA.