If you're losing the back end, stay in the throttle to keep the weight back there. Lifting suddenly will transfer weight to the front, costing you even more traction at the rear. Truthfully, in the Swiss Alps and Smokey Mtn, I hardly ever brake, except for the two sharp turns at the ends of the fast straights.
As Talentless said, countersteer, hard. Most of the rally cars are 4WD or FWD, so staying on the gas will also help claw the front end around. Once the car stops rotating out of control, you can back off the throttle a little to regain traction and to make sure you don't crab off the outside of the turn. You'll go through the turns sideways, but hey...
If the car does spin, give up. Let go of gas, brakes, and steering. It will be over sooner. Wait for it to come nearly to a stop before picking back up and continuing.
Good luck! Try doing the rallies in free run, using the Peugot 206. Just keep practicing until you get the hang of catching the car.
