If you would like to submit a short story for consideration, just send an email to: email@example.com. All stories should be submitted as an attachment and should not exceed 5000 words. If you want to submit a series, then each episode in the series should be no more than 2500 words.
You should also be ok with the fact that your story, once submitted, is free from all licenses etc. In short, you are simply sharing your work with the world for free. The credit you will get is your name at the end of the story and a link back to wherever you specify. Anonymous submissions are accepted as well.
Given the volume of submissions that come in. It might take a while to get a response. But if the story is really great, and need no editing, it will be posted within 3 days of submission.