Start with an all wheel drive car and go into qualifying online. Take the track painfully slow just to get a ghost car created. On the next lap go just fast enough to beat the ghost. Keep repeating trying to beat your previous best. Take your time.
Once you are at a point where it gets difficult to beat your best time, you should have the track memorized. Now start experimenting. Brake a tenth of second later on a corner. Take a corner in one higher gear, try it in one lower gear. Each time see if you gain or lose time against the ghost.
Also if you go off track and mess up, and you will, don't restart. Use the rest of the lap for crazy experiments and then get back to it on the next lap.
Once you have it dialed in, switch to your preferred car and use the ghost to hone it down to your best possible time.