On top of what everyone else has said, what helps me a lot is finding a decent marker for my braking point. if the game has a dynamic driving line then it can help you get a rough estimate for the braking point, but it is almost always very inaccurate. Usually there are brake marker boards at the outside of a track, but you can use anything that's in the right place, be it a kerbstone, some large, noticeable marks on the track, a service road that joins the track, a large bump or anything.
There are usually some dark marks just before a corner that have been made by other cars braking. these are where other cars have been braking for the corner so it is usually a good idea to brake there too. depending on the car that made the marks and the car you are in you may have to adjust your braking point considerably from those dark marks, but it is usually a good estimate for where you should be braking.