Here's some advice I use taking that difficult corner.
1. Brake early. This is especially true in higher powered vehicles, and vehicles with the engine situated behind the driver (MR, RR, some 4WD). Don't brake too early either, people can pass you on the inside or outside if you brake too early.
2. Apply brakes with a smooth motion. Sudden braking can upset the vehicle's balance, especially in MR, RR, or some 4WD vehicles. Also, try not to use full braking so you can leave some room for turning and stability.
3. Coasting through the turn after braking, rather than braking then accelerating immediately, is a good strategy some people use. It is a big turn after all (almost a 180).
4. Try not to feather (rapidly tapping) the brakes. This can also upset the vehicle's balance causing understeer.
5. Utilize the straightest possible line when approaching the corner and during the heavy braking zone.
6. This corner is a decreasing radius corner. Try using a later apex (later clipping point) by setting yourself up wider than normal. But be careful not to go too wide, or you'll encounter run-off or understeer.
7. When accelerating out of the corner, you'll need precise throttle control and steering response. Applying too much can lead to understeer (FR, some 4WD), or oversteer (FR, MR, RR, some 4WD). TCS and Force Grip Recovery (FGR) help in this department if you are having trouble with accelerating. I use neither when possible. You'll also hit those two consecutive sweepers right after that turn, follwed by a hairpin turn. So precision is still a huge part of turn 1 that affects the angle in which you take the sweepers (not officially turns) and the hairpin (turn 2).
8. You can try setting the brake balancer a little weaker in the rear. This may prevent most vehicles from fishtailing out under heavy braking into a corner. A good course to test this is at the High Speed Ring.
9. Downforce may be you biggest ally here. But remember, this is also a high speed course, so too much could be a bad thing.
10. Suspension should be set to moderately stiff to stiff. It is a fairly smooth track. Tire selection also makes a huge impact on cornering and braking.
11. This corner should be taken at 2nd or 3rd gear, depending on how many gears your vehicle has and their ratios. Try to keep the revs within the vehicle's powerband.
Note: I would've also suggested buying racing brakes, but they are mysteriously missing form the Tune Shop (upgrade shop).
I've watched so many people (alot more than none) lock up their brakes, understeer severely, spin out, or just plain missed the braking zone while playing online.