Best way to downshift?

[thstone]

For straight line braking, use the brakes not the transmission.

Prior to a turn use heel and toe to rev match and complete your shifting prior to the corner. A proper rev match means that you may have to wait for the car to slow to an appropriate speed to match the revs smoothly. Too early and the engine over-rev's, too late and the blip doesn't matter much. Heel and toe rev matching ensures that you are in the right gear on corner entry so you can control the car in the corner with the throttle (if needed) and so you can accelerate smoothly out of the corner.

With practice (and practice and practice), braking while heel and toeing is one continuous fluid movement and its like dancing with the car. I do it on the street all of the time without even thinking about it, its second nature now.