To enter compass calibration toggle the Manual / Auto switch ten times quickly and end at AUTO mode position. 

The green LED will light up continuously.  This indicates compass calibration mode.

(Although in this video it was toggled 11 times.  Still works. :D )

Horizontal Axis Calibration

Hold the helicopter by the tail and slowly walk in circles rotating the helicopter.  Try to keep the white LED on.  Walk around 3 to 4 times. 

As you walk around observe the LED.

If the white LED goes off then the helicopter's horizontal level is not consistent during rotation.

When successful continue with the Vertical Axis calibration.

Vertical Axis Calibration

Vertically hold the helicopter with the nose of the helicopter pointing downwards.

As you walk around observe the LED.

Rotate the helicopter 3 to 4 times while keeping the tailboom as vertical as possible.  Try to keep the white LED on.

Saving

To save the data quickly toggle the manual/auto switch 10 times.  Same as starting compass calibration.  All three LED should flash for 5 seconds indicating a successful data save.  Reboot the system.

To abort and not save the data then toggle the switch once.  The green light should be off.  Reboot the system.