Some if these have already been mentioned but this is what they do with full size cars:

Increase rear roll stiffness (stiffen or install sway bar, use stiffer springs)

Reduce front roll stiffness (soften or remove sway bar, use softer springs)

Reduce front toe in or create toe out

Reduce rear downforce (reduce spoiler angle of attack)

Increase front downforce (install spoiler or increase angle of attack)

Use wider front tires or a softer compound

Use a harder compound on rear tires

Consider adjusting CG fore of aft
^^ Experiment here ^^ on full size cars ones with rear engines tend to have more oversteer than those with front engines. Obviously you can't just move the engine but consider radio gear, batteries, etc.

If you want to try to drift around an entire track you can do what some people do. I don't know if it works with RC cars but works with full size ones. I will ruin your tires and may not work but set it up for only front wheel drive (if possible) and set the brake to drag a bit on the rear. Then just drive and try to keep it under control.