If you have defeated all 15 blacklist in career mode of NFS Most wanted game, you need to win last game of career mode which is called Final pursuit of NFS MW.
In Final pursuit of NFS MW game, you need to escape from the city (Rockport City). Only after successfully escaping from city, you will become the most wanted blacklist of the city.
There is only one road to escape from the city. That escape road is located in Rosewood area , that you can see in the given map. The escape road opens only after 5 minute of pursuits.
First you should Free Roam from another career account from Point Camden Area to escape road (old bridge) and remember the best route by practicing. The Best route is the way which passes from right side of bus stand. In this route you need not to turn to 90 degree to inter the escape road.
Now when final pursuit game start, spend first 3 minute in the Point Camden area itself. Drop as many structure as you can and immobilize police vehicle as much as possible. After successfully spending first 3 minute at Point Camden area (starting area), run into remembered route. Speed you car as much as possible, the only thing you need to give much attention is the upcoming road block. Hit the road block at weakest point. In two minute you will reach the escape road and you will find the road is open, move in the escape road (old bridge) carefully. Avoid hitting any thing, keep your speed high, to jump the broken bridge, your car speed should be high .