From Changi airport take the MRT (underground train) to Bugis station. The airport line is only 2 stops long, so all trains change at Tanah Merah station, trains come every 5 minutes, the whole MRT journey takes about 30 mins. After midnight the MRT isn’t running, but taxis are inexpensive (approx S$25 or 15 Euros) or if you’re not in a hurry the shuttle buses are slow and infrequent but only about S$10.
From Bugis MRT take exit B and walk up North Bridge Road (4-lane one way street, walk in opposite direction to the cars), turn right into Arab Street, then immediately left through the arch into Muscat Lane, then the 2nd small street on the right (the pretty marble-stoned pedestrian street, not the back alley service road). We’re number 55 Bussorah Street.
If coming overland from Malaysia, bus is much much better than train – try to get a bus that terminates at Golden Mile, from there walk 10mins down Beach Road, then turn right into Bussorah Street.