Here are some reference points and advice to help you master the parallel park exercise.
Pull alongside and slightly ahead of the car to be parked behind.
You need to be about 1 metre from the car.
Check all around to make sure it is safe and reverse until your door mirror is level with the front of the target car (as in this diagram).
At this point steer one half turn to the left (the steering wheel will be upside down) so that the car moves in a gentle arc towards the kerb.
When you get to the "turn in point", stop the car.
The "turn in point" is shown in the next picture
This is the "turn in" point.
Note that the BOTTOM edge of the kerb is aligned with the centre of the front door handle.
Every car is slightly different, and you will need to adjust how much of the front door handle is on the kerb depending on your own driving position.
Steer full lock to the right and reverse in slowly
Continue reversing slowly with right full lock, and when the car is parallel with the kerb, straighten your wheels.
Ask yourself if you would be happy to leave the car parked in this position. If the answer is yes, then the manoeuvre is complete!
Parallel Parking - When you're too close to the kerb!
If you leave the "turn in" too late, or steer to full lock slowly while reversing quickly, you will hit the kerb.
To resolve this, put full lock on to the left, check all around for other road users and pull forward slowly to straighten the car up.
As soon as the car is parallel with the kerb, straighten the wheels. In moving forward, the rear wheels will pull away from the kerb.
Parallel Parking - When You Finish Too Wide From The Kerb
Pull forward to the target car. Remain parallel to the kerb; DO NOT try to steer closer to the kerb at this point !
Select reverse and steer one full turn to the left.
Give the car time to come closer to the kerb, and then steer two full turns to the right (the first full turn will straighten the wheels, and the second will turn the wheels to steer the front of the car towards the kerb).
Don't forget to straighten your wheels when you are parallel to the kerb.