The company asked me to drive a pink car as a marketing tool. Did I like it? No—a blond girl in a pink car is a total cliche. But it had one positive impact: Little girls all dressed in pink came to watch the races and meet me. It made those little girls aware that they can race.

I've been racing cars since I was eight years old. You could say it's in my blood: My dad raced motorbikes and my mum met him when she bought her first motorbike from his shop on the west coast of Scotland. Today my parents run that same shop together.

When my dad raced my brother and I spent every minute on little Fun Karts near the main track. Soon my Dad stopped racing and bought us both little karts.

Driving karts turned from just having fun into my passion. I started at club level and by 18 finished 15th in the World Championships.

When I look back now, I never realized I was doing anything unusual. My parents supported me exactly the same as my brother and my mum never made me believe I was doing something different as a girl. My mother worked and supported my dad, while my dad also fully supported my mum. Theirs is an equal relationship and it led me to believe I could achieve whatever I dreamed of, regardless of gender.

I moved into single-seater racing (smaller versions of Formula One cars) and by 2003 I was the first female ever to be nominated for the prestigious "Young Driver of the Year Award" in the United Kingdom. I didn't win.

The next year I was nominated again, and at the big awards ceremony in London Sir Jackie Stewart (a fellow Scot and a three-time Formula One World Champion) presented the winner. All six finalists, including me, were on stage. He called out the names of the five other drivers (who were all male, of course) and then said, "Oh, it looks like we are missing the sixth driver."

I stepped forward and said in front of the big crowd, "My name is Susie and I am the sixth driver." He looked at me with a puzzled expression and then said with a small laugh, "Oh, that's right, I forgot there was a girl in the final this year." At that moment I knew I hadn't won, again. After the awards were presented Stewart's wife came over to me with a puzzled look on her face and said, "Why would a girl like you ever want to be a racing driver?"

Did moments like these affect me? Yes, of course, but racing is my passion and each time a comment like this has been said, I get even more determined to win.

Unknown to me, the boss of Mercedes Benz Motorsport was watching the awards ceremony. One year later, he remembered me and offered me a test in the Deutsche Tourenwagen Masters, the German Touring Car Championship. I arrived at the test and was mistaken for a member of the press and marketing team. Once I had made it clear I was actually driving the car, I got in and drove with nothing to lose.

One week later I had a Mercedes-Benz contract as a racer and an ambassador. A one-year contract extended into seven years. During my last two years the company asked me to drive a pink car as a marketing tool. Did I like it? No—a blond girl in a pink car is a total cliche. But it had one positive impact: Little girls all dressed in pink came to watch the races and meet me. Many fathers told me their daughters were never interested in racing until the pink car appeared. Yes, maybe I was playing into a stereotype, but it made those little girls aware that they can race.

Last year was my seventh and final season in the German championship and with Mercedes Benz. My gut told me more was possible. I had to move out of my comfort zone and push myself even further. Now I'm pursuing my dream of driving in Formula One (F1).

I am the development driver of the Williams F1 team and at the end of last year had my first successful F1 test. This July I will drive against the best up-and-coming drivers in a young driver test. People have said I will simply embarrass the team and it's not possible for me to win. Sir Stirling Moss, a retired F1 driver, recently said in the press that women do not have the mental aptitude to drive an F1 car. I will prove him and others wrong. But I'm not on a mission to show that women are better racing drivers than men. I was lucky enough to find my passion in life and I am simply following my path.

I got married two years ago to a wonderful man. He used to be a racing driver, too. He remembers that years before we met, he heard about a girl who was beating all the boys. He ended up marrying that girl. In January he was appointed as the new Mercedes Benz Motorsport boss and continues to support me through all the ups and downs. I know there are not many men who would be so supportive but he always pushes me to be the best I can be.

I didn't realize that my story could be so inspirational to other women until my brother (who didn't follow me into the world of motorsports but became a film director) made a documentary about my racing for the BBC. It aired some weeks ago and the incredible response from women who were inspired by my story shocked me.

It led me to think more about the issue and read Lean In. I could relate to so many points she made. I work in a mostly male environment, too, and as women we are all facing the same challenges. We need to help each other, lean in and simply be the best we can be.