Shut Irrigation systems for winter. Winter sprinklers switch off https://www.watercorporation.com.au/Help-and-advice/Watering-days/Winter-sprinkler-switch-off/Winter-sprinkler-switch-off

Broadleaf weed control. If you have a heavy infestation of  broadleaf weeds, you can spray these with Bromoxymil if you have a soft leaf buffalo lawn, or Dicamba if you have a couch grass lawn. For the different varieties of turf weeds, check out this link https://www.environmentalscience.bayer.com.au/~/media/PRFAustralia/Resources/Turf%20Poster.ashx

• If Wintergrass is a problem, spray now, use a product such as Amgrow’s winter grass killer. Unlike the pre-emergent this works on contact with the actual weed.
• Aerate areas of compacted turf. Compaction should be addressed by circulating air through the soil under your turf. To achieve this you can use a spiked roller, a pitchfork, or even spiked shoes to break up the soil. You might also wish to consider the use of gypsum, if you have a clay-based soil, as this will assist in separating your soil, loosening any clay that might be in the subsoil.

Mow fortnightly at 15-20mm as per turf variety, refer to https://tgawa.com.au/turf-varieties/