Know what you (don't) want!
I have faced numerous circumstances in my past where I had to be clear about my choice or preference. The magnitude of these choices vary - from selecting an ice cream flavor, to buying a car to deciding on a job/career. In such situations, my tendency - like many others, I'd think - is to be as wide-ranged as possible. I can't go wrong by being broad, I thought. I was also worried about shutting down opportunities by being too narrow. Unfortunately though, this tendency to be broad, led to vagueness, and a lack of specificity. Contrary to my belief, being too broad (and vague) didn't lead to opening more doors, but rather left me with lesser, or poorer choices. It turns out that being specific allowed my choices to be matched more closely and quickly to what was available/possible.
Over the years, I have learnt to be more specific without worrying about what choices I may be eliminating as a result. Of course, I had to do my 'home work' to make sure I knew what choices were available to me. I also had to do some serious thinking - to be clear about what I sought, and what I wanted to stay away from. And, I had to be bold about conveying my choices. Just having this clarity - especially about what I didn't want/seek - led to quicker and better choices to come my way.
Currently, as an independent consultant, I am putting this to full use. I have narrowed down my interests based on my skills, experience and passion. I have avoided the trap of taking on projects that didn't fit my interest/expertise. This is serving me very well, and I intend to continue doing so.