Please help me - I'm clueless!

[RamsayBoltonsConscience]

I haven't been on a plane since I was 15, I'm 50 now and next year I am going to Australia.
I'm really fortunate that my step father has a house in Byron Bay and he and my mum will already be out there - I only need to sort out my flights.
This is pathetic but I'm not sure where to start! Ideally, I would like to have a couple of days in Singapore either on the way there or on the way back.
Can someone just give me some pointers on the best way to do this? Please!

Go on a search booking site such as expedia which is useful for finding out which airlines operate which routes. You can also do a "multi-city" option to include your stopover on that. But then I would probably book direct with the airline if the price is comparable. Also sign up to the airline's loyalty scheme as going that far you tend to get a fair chunk of reward points towards another flight.

i get you, there’s so many ways to make bookings.

I prefer to book flights direct with airlines because if anything untoward happens the booking is direct with them, others will use trailfinders or dial-a-flight.
each to their own.

make some decisions first, dates of travel ,whether you’re stopping at Singapore on the way out or back.

decide whether you book yourself or use a third party.

either way, do some pretend booking on airlines such as Qantas, BA, Emirates to get an idea of prices for your dates.

changing to mid week flights could be cheaper.
good luck

I would do very similar to emma.
I'd search using Google flights, identify the airline I wanted to use, then book directly through that airlines web page.

Only thing I could add to what's been already said is to use the "flexible dates" feature (if your dates are flexible obviously!) so that you could find the cheapest prices around the time you want to fly

Look for flights on Skyscanner

Flights are cheapest if you avoid holidays like Xmas, Easter, school holidays, so play around with the dates

Cheapest if you land & depart from the same airports both ways

I prefer to fly at night for long haul

Check your passport is in date
Buy travel insurance when you book the flights
Get all your covid vaccinations

Brilliant, thank you!

I'd look for a few days stopover in both directions.
We went to NZ a few years ago with just a change of plane, it was awful!