First of all decide about the plot of the story along with the characters such as the protagonist and the antagonist, making sure that a short story does not involve so many characters.
You should either start by straightway describing the protagonist or the antagonist, doing something good or bad as often shown in movies so as to grab attention of the reader.
Make sure that you do not use more than one single paragraph to describe the character, may it be hero or the villain and make the story move to the next part as early as possible.
Create a situation by bringing in some suspense to sustain the attention. It can be a murder, kidnap or an accident the cause of which is unknown.
Now bring the hero or protagonist in a difficult situation where he has been trapped or being tested by the antagonist in a way that the reader feels unlikely for the protagonist to find a way out.
Once the protagonist is in difficult situation, describe the struggle for getting out of it in such a way that the suspense is there along with danger and thrill.
Just like an unlikely narrow escape, make the protagonist get out of the trap set by antagonist followed by putting both of them face to face with each other.
Involve the characters in some kind of a combat or a challenge in which the protagonist or the hero is on the verge of getting defeated by the villain.
All of a sudden, out of nowhere the hero propels a certain defeat into a triumph and wins the battle over the antagonist.
After the protagonist has come out as a winner having done through immense struggle, end the story with a good moral lesson.