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Heel and Toe Downshifting and then practice!!
I used to dread downshifting before I learned what Heel and toe meant. Now I am getting to the point where I can do it smoothly and quickly enough to avoid jerking the car.
And contrary to what others have said, I feel the contour pedals are set up just fine for heel-and-toe action. (I'm talking about the stock pedals, I've not driven a car with aftermarket aluminum pedals.) Now I am in the habit of braking with the left side of my foot so that I can tap the throttle if necessary for a downshift.
Double clutching, if done right, will eliminate almost all wear on your drivetrain components. However, it really isn't necessary on modern cars with fully synchronized gearboxes.
Also, heel and toe is only necessary if you need to slow down while downshifting (like for taking a corner). Otherwise just hit the throttle when you downshift and match revs for a smooth shift.
