The process of writing a successful short story is long and can often be complicated. The first thing to do is begin to plan the story. You need to come up with a general idea of the plot. The most important factor to consider is what your conflict is, and why this conflict should interest the reader. You should also plan who your characters are and how they will behave.
One you have a general plan of the story you should create a draft. You need to have an exposition, a rising action, a climax and a falling action with a conclusion. You need to build suspense about the conflict, and develop the characters' personalities.
If you are satisfied with your draft, the next step is revision. You should read your draft several times in order to make sure it has no mistakes and the story is compelling. It is a good idea to get other people to read your draft as well.
Finally, after these steps are completed, you are ready to publish your story.