How do you solve a 4x4 Rubik's Cube?

I used this series of video's on youtube.com:

http://www.youtube.com/watch?v=v4hXzxcRtTY&feature=channel

but if you don't like to learn it from a video, use this website:

http://www.speedcubing.com/chris/4-solution.html

I highly recommand to first learn how to solve a 3x3 Rubik's Cube, because at some point of the 4x4 you have to solve it the way like a 3x3, and that part is not in the video or at the website.