Renting a proper aerator machine costs bucks. Plus, my yard is relatively small and laid out oddly (partly including a 45-degree slope, and a sunken area.)
So, would it help to just do it manually with a large fork? How far apart, and how deep? The soil is rather clay-ish, although thoroughly watering it helps when digging garden beds.
I have already added lime and fertiliser in the past couple months. And just yesterday spot-treated some broadleaf weeds with Roundup ("Die! Diiiiieeee!") This place was neglected before I moved in.
It is (an especially cold) springtime in this part of the world, and I will overseed when the weather gets better in a month or so.