Practice makes perfect, but to achieve perfect you have got to know what the aim is.... so, what I do is watch the racing and see what people do on parts of the track and copy it - not all of it though, only what your skills will allow. So start with staying on the racing line, then carrying corner speed, understanding about weight transfer and how this effects the car when accelerating and decelerating - then as confidence improves you'll be able to start going for it over the jumps and technical sections. Over time you'll develop your own techniques as copying someone who is quick won't always be quickest for you.
All the same principles apply to full size. I was helping a lad a while ago who was stamping on the brakes and nailing the power, he had a 300bhp Nissan as his full size car, so I said to him to imagine driving his Nissan like this, he got the idea. To achieve this, you may want to reduce your throttle curve and reduce your maximum brakes. But find your own preferrences, what suits me may not suit you
So much happens per lap that you have to make a million decions per second. So don't go hell for leather as the car will just crash before you can react while you are consciously thinking about it, take it easy. With practice, the basic decisions come naturally and then you'll start being able to put gradually faster motors in.
Chris