HOwl, if you want to write better, expand your vocabulary. That is a major thing. Also, I'm not sure if this applies to everyone, and i'm sure it doesn't even work for those who it applies to, but growing up, I've learned how to mimic multiple personalities. To become someone and see everything in a different way. It's a good way to develop characters and the story as it progresses. No one wants to read a story where all the characters sound the same. A tip, read more and remember what you read. I have never been to writing college and the closest thing i have to a writing class is a creative writing class i took senior year of high school. I've been writing stories since 5th grade. Like Asia said, it's trial and error and a lot of critiquing. Though it'll take longer, always think about how it can be improved. My books, Kin Chronicles, is written in four stages. This might help:
Stage 1: Story overlay (mapping. plot. subplot. characters, etc.)
Stage 2: Rough Draft
Stage 3: Final Draft
Stage 4: Final Print (typed up, all prior stages are and must be hand written.)