Depends on what car, what class, what surface, what track.
You can go to the manufacturer's website and download a setup sheet that resembles your track. Or you can ask the fast guy at your track how his car is setup.
The kit setup should be pretty decent while you get the hang of driving on a track. You can get tips from the local racers about what will make your car handle better and adjust from there.
I'm sure someone will link you to a suspension tuning guide (I don't know the links) which you can study on so you know what is supposed to do what. Just knowing is part of the battle, takes tons of time and practice to know when and what to change.
When I first started racing I always thought there was a magic setup that would make my car fly around the track like it was on rails. Never found that setup b/c it doesn't exist, and years later I'm still learning everytime I am at the track. What I mean is you can adjust till your fingers fall off but you still have to drive the car properly.
And now is when the more experianced racer says.."slow is fast."
That means drive only as fast as you can stay in control of your car.
Hope some of that helps