The structure of the short story is a bit different then that of a regular story. For one you do not have the time or luxury of taking time to develop the protagonist. It must be done quickly. The reader must be drawn into the story almost immediately. Novice writers are often given, this advice.
1) Put a man up a tree 2) Throw stones at him 3) Get him down
Short story writing is not very dissimilar to writing any other type of story. You will first develop your protagonist, present him with a few challenges to get past, and then provide a way for the protagonist to prevail over his challenges.
It is very important to make every word count when writing a short story. It will surely be tempting to show of your gift with words, your descriptive writing skills or your skill with dialogue but dont do it. Every extra word that is not needed only waters down the impact of the story.
Many short stories happen in a short period of time, or are revolving around a single very important event in the main characters life. You will want to focus on this time and event carefully, simply because it will drastically affect the outcome of your short story.
You will want to ensure that your reader is both enchanted and delighted after reading your short story. They should be surprised at how good your short story turned out to be. The most important element in writing a short story is to be sure that your reader does not feel cheated. When your reader offers you their time, you need to do everything you can possibly do to ensure that their time was well spent.