Tip number 1 would be fly Qatar in future as their afternoon arrivals into east coast Oz are far better for the body clock than an early morning arrival.

But my advice to your question is pack a change of clothes, maybe even three shirts and underwear etc. The change feels the closest thing to a shower if you don’t get the chance in Singapore.

Also eat the lighter options on the menu and drink, drink, drink!! (Water that is..)