Melbourne Centre, ABC, Cessna 172, taxiing location, to destination, request code
ABC, squawk 1743, contact me airbourne for clearance
1743, ABC
ABC, airbourne location, passing altitude, climbing altitude, request clearance
ABC, you are identified, remain OCTA, contact approach on 123.45 for clearance
OCTA, 123.45, ABC
Melbourne approach, ABC, request clearance
...
(variations are inevitable based on locations)