This is one of the challenges you have to complete in campaign mode. This one is fairly easy if you use what you learned from the untouchable achievement and don't hit any walls. Start with a good start by getting a 97+. From there on try and hit every orange line in the curves to gain more speed. If you do this, you will become faster and more unstable, making you more likely to hit a wall and give them the lead. What you need to do is as soon as you get out of the curve, use the steering stick to center yourself and avoid a collision. To make sure you hit the orange lines in a curve, use the lean buttons and to ensure you get inside of it.