"Buy stuff in the city. It is cheaper than duty free in most cases then charge it with your card. Head for the duty freebooths (normally at the arrivals area before you drop your bags) to get a refund"
"If you are going to board a flight from T1 try to come in a bit earlier. A lot of the "OFW flights" are scheduled early and the express lane of OFWs many not be open. OFWs have more documents."