ClivePwned
Member
There's literally a train line from Domestic to the CBD (Central, Town Hall, Wynyard roughly). Just go to the ticket machine, hit the button for the station, pay the cash (or go to the ticket window, domestic is usually open i think).
In fact, I'm fairly certain the Domestic Airport's station name is just Domestic Terminal or something.
IIRC there's a train station at the airport. You should still be able to buy a paper ticket from a machine - they accept both cash and credit/debit card. However, you can always opt to buy an Opal card from the train station. You can load it up with cash at the train station and then press it onto Opal terminals at train stations and on buses and trams - you just press it on the Opal machine at the train station you get on, and again after you get off. You can either recharge it online (you'd need to set up an account on Opal's website) or at train stations and places like 7-11.
Here's a website for Airport Link which will give you the schedule for the trains running from the domestic terminal into Sydney. They even have a video for getting to the domestic terminal train station and a video on using the Opal cards.
Hope that is somewhat useful.
cheers