To really explain who you are, you have to explain who you are not.
One of the difficult things about any profession is marketing yourself. You have to convince colleagues, customers, partners and employers that you are someone worth doing business with.
As an established employee, this is not that hard. Your colleagues get to know you, the things that you are good at, and the things that are best directed to others. You can be reasonably honest about who you are.
If you are looking for a job, or working as a consultant, it is much harder. The employers and clients do not know you. With all the competition for your services, you must not admit any weakness. You have to be all things to all men. You have to be a great team player and capable of working on your own, a great manager and great at following the direction of others, innovative and good at following standards, and so on.
The problem with this unremittingly positive viewpoint is that it does not really explain who you are at all. If you are all positive, you will mismanage expectations or just not seem credible.
Somehow, to give a more accurate view of ourselves, we have to communicate what we are really good at, and what we are not so good at, without actually presenting this as weaknesses.
One way of doing this is to present yourself as a set of preferences. To show you what I mean, here are my preferences.
I could have listed a set of weaknesses - my low patience with project management, a lack of detailed knowledge of products and infrastructure, and a less empathetic approach in my communication. But by explaining these as preferences, it paints a more positive picture of who I am, without conveying a sense of weakness.
What I found really good about writing this is that it made me more confident. I can be honest, without either underselling myself or mismanaging expectations.
To market yourself, you need to be able to explain who you aren't.