I'm not sure I know a good answer, so I hope some of this might help... and amuse.
Don't bother with computer games for practice as you don't get any sense of what the car is really doing. You end up being great at a track on a computer!
Local spaces are fine, so lay out some cones and drive around them. Each run, change something on the car to make it not just driving practice. If you can have a buddy who can wield a stopwatch, that really helps show what the effect is of changing your line and speed.
Masami Hirosaka used to practice regularly in a dance hall. Two of his regimes are interesting! He would lay out some cones in the form of a basic, simple circuit. He would then turn to the mirror on the wall and drive the car round the track by looking in the mirror!
The second one was to lay out a large, fenced area on the floor. Into that he would put several of those little battery-powered cars that turn around when they hit something - a bit like having a flock of random bees in a pen! With his simple track laid out he would drive the track avoiding all the random little cars!
If you think driving with his feet was clever...
