Seeing as this game is going Games With Gold in late December 2016, I thought I'd re-write my guide for this achievement. My original guide will still be here too.
This is the final licence you get from the game. For this, you'll need to win every event in the game. If you have completed an event, the event will show up on the map with a tick. There are 5 types of events in the game:
2. Road Rage
3. Stunt Run
4. Wanted Man
5. Burning Routes
Best way to tackle this would be to go through each type of event one at a time. It's been a while since I've played the game so, I am unsure if you can filter by type of event, someone please confirm in the comments below as I do not have the game on disc any more. It helps if you have found all the races, they're mainly located at intersections across the city:
Quick note, burning routes can be done as they are unlocked. When I got this achievement, I had been doing this. By the time I went for my elite licence, I had already done 25 out 35 burning routes so, instead of doing all 120 events for my elite licence, I only had to do 95 events.
says in his solution, if you have the Big Surf Island DLC, do the burning route for the buggy to unlock the Dust Storm Super Turbo. Using this vehicle will pit you against the normal version in any event you enter giving you a significant advantage.
Any negative votes, please state in the comments below on how I can improve the guide. Thanks.ORIGINAL SOLUTION BELOW
For this achievement, you do NOT have to leave the burning routes for the license. You can do them whenever you want to, it will not affect the achievement. I've completed 25/35* burning routes and for my Elite License, it says that I only need to win 95 events.
So what I would recommend for this achievement is to get the burning routes done and dusted as you take down the cars roaming around the city, this will leave you with less work to do for your Elite License.
(*correct number of burning routes completed for me on 09/04/2012)
EDIT: As a little side note, I recommend that you do all events for each type of event before moving on to the next type of event. I did the races first, stunt runs next, road rages after and then finished off with the marked man events. I completed the burning routes as I unlocked the cars.