Hi @bax,
Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.
There are 3 steps I would recommend, dethatch, aerate and top-dress.
The layer of dead grass is called thatch. A layer of dead and living organic material, like grass clippings, stems, and roots, accumulates between the soil and the actively growing grass blades. Removing this layer of material will help the grass breathe and absorb nutrients more effectively, which will in turn create a thicker healthier lawn. You can remove this thatch using a Cyclone Timber Handle Long Thatching Rake or Ryobi One+ 18V Brushless Cordless Scarifier OSF1835BL.
Once your lawn has been dethatched, it will look quite bare and, in most cases, extremely dry and brown. Do not worry, this is all part of the process.
Check out How To Dethatch Your Lawn for some guidance on this process.
Now that the thatch has been removed, you should aerate the soil with a Trojan All Steel Spiked Aerator.
Check out How To Aerate And Top Dress Your Lawn which also covers the final step, top dressing.
Use a high-quality top dressing mix such as this Seasol 25L Lawn Top Dress Mix. Apply a layer approximately 10-15mm thick and spread with a Cyclone Top Soil Spreader aiming for a nice even surface.
Once top-dressed, water your lawn well using the mist setting to avoid any soil runoff.
Given a few days of sunlight, the lawn will start to repair and fill out and within a few weeks it will look brand new again.
Let me know if you have any further questions.
Jacob
