The thing I still get a bit cautious of now days is when your doing 140 down a straight and your less than a meter from the car infront. You dont know when that person is going to brake. You know were you are but not them, they could brake much earlier. Other than that (for me) it was just a case of getting onto the servers, and just going for it. I've learnt you cant (And wont) win a race at T1, usualy I would try and brake late, take a awkward angle and get in a position, now I just take it as it is, if im next to people, there we go, just coast it around at a safe speed.
Its just a case of experimenting dude. The more you try stuff, the more confidence you will have.