There are three ways I generally start writing a new story. Most often I start with the scrap of an idea, almost as often with a character, and once in a while a setting grabs me and starts the ball rolling.
There is a fourth way to get a story started, and it's one I've largely ignored. That method is to begin with a theme in mind. I've avoided this method of story creation largely to avoid writing fiction with a "message". I write to entertain, not educate and having my writing come across as a sermon does not appeal to me.
In researching theme and how best to use it I came across some interesting takes on theme that made me think differently. I now believe that starting with the theme in mind does not have to lead to preachy fiction at all. I also believe that the sooner you have a handle on your theme the faster and easier your writing will be.
Check out Know Your Theme and see how redefining theme can help your writing.

I like the idea of starting with an idea, I will keep that in mind!
Thanks
I start my stories with an action. It helps me to get right into it.
A great place to start is a trip through a newspaper or listening to the news while driving. An idea starts
Then as I drive,listening to music…the story starts to develop. The problem is trying to remember all the details when I get home.
I try to create an environment in the beginning so as to enter the main theme at the earliest! Normally stories are meant to be read in one sitting and need to be within say 1000 to 1500 words.
Effectiveness of the story lies in the fact that the reader understands the basic facts without applying much of his grey cells and appreciates it.