To Lin
The best place for clothing is Binwang Market. For the flight time is so early, you can not take the bus. As the first train at 1am will run more than 3 hours to Shanghai South Railway Station and you do not have time to go the the airport from the railway station. So, I suggest you come to Shanghai in advance. Yiwu has direct shuttle bus to Pudong Airport and you can also take trains or bus to Shanghai and get around, then take the airport bus or subway maglev train to the airport too.