There are several ways. One is to post them in the stories section. You will have to register in that section to be able to place a story but then it is just cut and past. Warning, this section does not play well with formats and will smash words together.
Second, you can post in the writing forum. You would create a thread with your story. If you would like comments, just ask but don't necessarily expect them.
Finally, under the writing forum, there is a story subforum that can only be accesed by members to protect somewhat your publication options.
Anyone of these will do.