Decide between electronic and print publication. Publishing short stories has become much easier than ever. There are thousands of outlets for short stories, but before submitting to a publication, you should set your expectations realistically. Will you be happy with being published electronically (i.e. on a website or other e-publication)? There is a thrill that comes from seeing your name printed in an actual magazine rather than online. Is your goal to see your name in "print," or build a portfolio of writing credits? If you want to gain experience and credits as an author--which can help you obtain a literary agent for a longer work--online publishing can be a real asset.
Decide between being paid or not. The vast majority of online publishing outfits do not pay for short stories, but several do. Will you be happy with publication even if you are not paid? While there is slightly more money to be made being published in a print magazine, these periodicals are often much harder to break into. For some, even a stipend of $5.00 can feel like gold. It's up to you where you want to set your sights. It's probably best to create a list of top paying publications and submit to them first, then steadily work your way down. A published story is still a credit to add to your query letter if you pursue publishing a novel or other longer work.
Offer a great product. The single best way to have a short story published is to write a great short story. Short stories generally focus on plot. Does your plot move quickly, following the traditional story arc of exposition, rising action, climax and resolution? Is each word the best word you can use? Are the characters richly drawn and inventive? Share your work with other writers and ask for realistic feedback, then rewrite the story until it shines.
Follow directions. There are a number of sources listing short story publishers both online and in print. The Novel and Short Story Writer's Market is published every year and provides excellent resources for publishers of short stories. Several websites, such as www.duotrope.com, offer free search engines to locate the best publisher for your work. When using these resources, follow the instructions given by the publishers. Some will want the entire story mailed to them, others may want only an e-mailed query. By following the rules set by each individual publisher, your chances for publication increase dramatically.
Be patient and keep writing. One story does not an author make. If you are determined to be a published short story author, you must write short stories! The publishing game moves very slowly; spend your "down time" between submissions writing more stories. This will not only give you more chances at publication, but will help you hone your skill as well.