Write a short-short story of 300 - 2,000 words. The story should have a clearly defined beginning, middle and end, and should aim for some sort of aesthetic effect, whether an interesting story, a moving study of character, an exciting use of language or some other aspect of writing. There are few specific requirements, but the story should demonstrate that you have been thinking about and trying out some of the purposes, forms, processes, effects and motives we have been discussing.
Write a story of 2,000 - 4,500 words (the upper limit is approximate; feel free to go over, but do not go way over). As with the short-short, this story should have a clearly defined beginning, middle and end, and should aim for some sort of aesthetic effect. All parts of the story should contribute to its goal. All elements should be developed as fully and effectively as possible, within the context of the story's specific goals: situation, characters, dialogue, setting, pacing, point of view, etc.
In order to write a successful story, you should apply the work from the exercises (the skill, not necessarily the finished product), and revise significantly on your own.
Most of any writing process is actually rewriting. Many writers find that the first draft is almost useless in itself. It contains just enough of truth to make the final work, however difficult, possible.