Add lots of organic matter and till it in.
I have a local high end stable that has no pasture and uses lots of wood shavings for bedding. They feed high quality hay so I don't have much weed problems with it.
I also have made a deal with the local tree trimmers and let them dump their shredded limbs.
It was into the 4th year before my heavy gumbo clay started getting friable and working good.