What Dave said.
The slides you didn't want to initiate were just from too much throttle too early. The spins were because you didn't get off the gas earlier enough, as well as (in some cases) not applying enough opposite lock. I don't think this is really about car set up, yet.
Take a look at my vid from last year:
You should be able to hear me give it a prod of throttle on entry or near the apex, then get out of it almost completely once the car has started to slide. I only reintroduce the throttle when the car has settled into its slide, so I can hold the angle (or increase it ). Finally, don't be afraid to let the steering wheel slip through your fingers if it's a big slide. You'll find it less frantic, but remember to wind the lock off as you recover the slide.
Keep practising, it's lots of fun