Know the Write Rules before you Break them
Grammar, punctuation, word choice: these are the tools of writers.
To write effectively we need to know when and where certain punctuation is used. A misplaced comma can change the entire meaning of a sentence.
Word choice is critical. Using a word incorrectly can cause confusion, embarrassment and loss of credibility.
However, there are times in fiction writing that breaking the rules makes the writing more powerful. The only way to know how to effectively break the rules, is to first understand them.
Grammar Girl has an excellent, easy to use website for any writer to learn about these essentials. In addition, you will also find information on proofreading, commas splices and so much more. I highly recommend it.
Google search: grammargirl.quickanddirtytips.com