Question about Amazon Prime Free Trial

[VA703]

I plan on ordering a Xbox 360 arcade.
It says that if I sign up for Amazon Prime Free Trial then I can get free 2 day shipping.
My question is this, If I do sign up for it how do I cancel the trial?
I just want to sign up for the free 2 day shipping and then cancel.
Or do they end up charging you anyways if you cancel the trial?
In other words "Scamming" you.

[Richter]

http://www.amazon.com/gp/help/customer/display.html?nodeId=13819211&#cancel

[Scorch]

No, there's no charge.

I signed up for the trial on black friday and got free shipping for a while, then cancelled it.