When it comes down to how to have a successful career, I tend to think it only comes down to a few key things. It's an odd paradox because I tend to think that it is not easy to achieve what I have but at the same time I tend to think my job isn't that hard.
The one thing that I've noticed in all the jobs that I've had is there is a lack of people who have strong opinions. I'm not one of those people. If you know me, you know I have strong opinions. Right or wrong, I'm going to have something to say on most topics. Most people sit quietly and just accept the opinions of others. I can't tell you the number of meetings I've sat in where nothing gets done because nobody has an opinion on something. It also is startling to think about the number of times I've seen someone win an argument because they had such conviction when they spoke only to be absolutely wrong.
To be successful at any job, you have to be a leader. Being a leader doesn't mean having 20 people report to you, it really is about charting out a course for others to follow, and then getting those people to follow you. Sure, it is easier to do if you are responsible for performance reviews for those people, but being someone's boss doesn't mean you are leading them. It just means you get to tell them what to do.
Most companies have leadership voids. It's odd because most people want desperately to move up the ladder, yet so few are willing or understand what it takes to do this. Probably the first and most important steps is to learn to form an opinion on any decision that needs to get made. Most people are paralyzed when it comes time to make a decision. Don't be one of those people. It is far better to be on the wrong side of an argument than to always stay in the middle. You will inevitably make mistakes, that's life and people expect it. However, it just takes that one great right decision to propel you forward.
This is not to say you should randomly pick a side and argue for it. I've seen people do that too. They just end up looking like idiots over the long haul. You have to think about you are arguing about. You need to use data to drive your arguments. Good analysis is key. But, after you analyze the date, you need to have strength in your convictions.