This requires you to score over 2 million points in any event. Load up the Driftkhana map, Sendai. Depending on your skill you may need to use a different vehicle than the one used in the video. Simply keep your multiplier up by drifting and not hitting the walls.
Here is a video guide with English commentary!
Here is a playlist of guides for this game!
https://www.youtube.com/playlist?list=PL-HeW6XkKdUJ-DlF7R_tS...