>>2931509 (OP)Cover it with cardboard.
Vinegar (20% horticulture), salt, and dawn, dissolve the salt fully before putting it in your sprayer.
This will kill the green and leave behind semi salted soil which should help prevent growth for a few months.
You can omit the salt for a weaker spray that you can seed next day.
If you want nothing to ever grow there throw down salt. This is nice when you plan to build or need a area clear for foundation work for a shed or something.
Thats about it beyond manually scalping the soil. If you want to do that it's slow and tedious but if you swing a flat pickaxe like a golf club you can basically just draw strips and cut up sod.