Get the first place record in all fifteen events to unlock the Extreme difficulty setting.
To not get gate faults, stay between two gray lines.
On the Ski Jumping event on either the normal or large hill, if the circle on the arch strays to either the left or the right of the center, use the Left Analog-stick to move it to the opposite side of the center to counter-balance yourself. This will take effect when you take off. If done correctly, you will stay level and achieve a far distance.
At the start of any Speed Skating event where you need to tap X and Circle rapidly, use an object, such as an AA battery, instead of your fingers. You should be able to tap them faster than you would be able to normally.