The first thing you need to consider in creative writing is your topic choice. While technically you can't be marked lower for your topic, something markers look for is creativity. If a topic is the first one you thought of, chances are, 70% of the class is thinking along the same lines. It's difficult for your work to stand out if you are writing about the exact same thing as everyone else. It's also important that you pick a topic that you can actually write about it with purpose, and write enough to meet the requirements. When we were working on creative writing for the HSC we were told not to pick any of the following topics: school, holidays, family turmoil, death/suicide, peer pressure, fights with friends, etc.
They're pretty weak topics. And your character probably shouldn't die.
As for the requirements:
If you write about the school certificate, how are you going to use imagery effectively? It will be difficult. For prelims we had a text called Sky-High, about this girl having a nostalgia moment basically. It was really well written, especially her use of imagery: she used the clothesline in her backyard as an anchor point around which the rest of the story revolved. Then she used the clothes on the line as a feature to link the past and the present together. Look for clever things like that to use in your story.
Organise: plan your story's purpose before you start. You need to show an understanding of your AOS by exploring your ideas. You might be comparing two different ways of thinking, anything really. But it is important that you use the protagonist to do this, and show character depth and plot development. Once you have your idea, it would be a good idea to plan the major sequence of events, then fill in the gaps (your selectivity.)
Don't put padding in. If a sentence doesn't add anything, take it out. Markers notice these things.
Good luck. Maybe you could post your story up once you're done writing it.
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