When I started in banking, I was not a nice person

Finance is a dirty, dirty, dirty game. Elbows are sharp. Knives are out, and plunged into backs of colleagues and bosses. Buses are driven over ambitions and finer sentiments. If you're the industry, you'll know what I'm talking about. Nor does it get any easier as you get more senior. If anything, it's even harder at the top: the higher you get, the more that success is about politics as well as hard work.

As a young person coming into banking, it's easy to get overcome by this culture. When you start out at a leading bank, you're going to feel like a Master of the Universe - after all, up to 500 other people were chasing your job. You figure that you must be special. You feel like you could do anything and the world is at your feet. This feeling intensifies as you make your way up the junior ranks.

For me, things came to a head when I made vice president (VP). People don't really discuss it, but VP is one of the most political roles in banking: you need to manage all the juniors working underneath you, and you also need to manage the expectations of the demanding managing directors above you. It can be tough. It's easy to make mistakes. When I was a VP my problems began.

I knew nothing about politics. I had a sizable ego after spending several years thinking I was something special. I plunged in. I started taking sides, stating my opinions and grabbing power wherever I could. I was completely ignorant of what it takes to make friends and allies in a large organisation - and I had no interest in doing so anyway. Why did I need allies when my strategy was working well? I got promoted, my career was progressing. I was pretty pleased with myself.

And then everything started going wrong. Slowly, people started hearing what I'd been saying about them behind their backs. The partners I was backing left, and I was left exposed. The MD I'd been bashing confronted me about what I'd been saying about him.

Things came to a head when by badmouthing became apparent to all concerned. I lost control. It's like when you're in a snow storm and your car starts sliding. I was frantically turning the wheel right, trying to undo all my badmouthing, but the car was going left. FAST. Then, BOOM. Collision.

I'd committed what is known as a "CLM": A career limiting move. This is not to be confused with a "CYA": A cover your ass. I had left my ass completely uncovered and all of a sudden I was out in the cold. After long years of feeling and believing that I was something special, I clearly wasn't. It didn't feel good. But it did teach me a few lessons that I urgently needed to learn.

My biggest lesson was that when you work in finance, you need to keep your ego in check. Playing politics will get you nowhere. If you want to get ahead, keep it clean. Keep your head down; make money. Also, know that you will make more money more quickly if you make friends. Always talk positively and well of people. You should be the person you want others to look up to. You should be the person you would be proud to be.

I'm not saying ignore the politics altogether: just ignore the negative politics. Stop bitching. It may make you feel like you aren’t one of the cool kids. It may make you feel like you aren’t a Master of the Universe, but staying out of politics will mean that you will stay in control of your life and career rather than sliding off the road at 60 mph. I know, I learned the hard way.

What I Learnt on Wall Street is an education focused business founded a group of Wall Street veterans from the best firms determined to help the next generation.