Day number two continuing on Commandments: Treat yourself like a professional, seriously.
Take a look what I mean:
2. Act like a professional
To be taken seriously as a writer, you must act like a professional writer. That means whenever you deal with other professionals in the writing business, such as agents, editors and publishers, you should act the same as you would for a job interview, and present a professional appearance. This is especially important in cover letters and manuscript preparation.
First, proofread for grammar, punctuation and spelling errors. I have heard many editors admit they sometimes reject a manuscript within the first few pages solely due to the number of grammar, punctuation and spelling mistakes. After months or even years of hard work perfecting your story, novel or screenplay, it would be a shame to have it rejected just because you didn’t bother to check your spelling or fix a sentence fragment. And don’t rely solely on spell-checking and grammar-checking computer programs—they make errors all the time. If grammar is your weakness, then find someone, either a friend or professional, who can proof the pages for you.
Second, perfect the format. The place to be creative is in your writing style, not the manuscript format. Avoid fancy fonts. They’re distracting and hard to read. Stick to standard margins. Narrow margins crowd the page and slow the story’s pace; broad margins make it appear as though you don’t have a substantial story. Don’t design your own cover. It smacks of desperation.
Third, polish the cover letter. Just tell the editors what they need to know. That includes: (a) a brief summary of the work, one to three paragraphs, and (b) anything about yourself that might be relevant to the work (if you’re submitting a police procedural novel and you’re a journalist who worked the crime beat, that’s relevant). Avoid overhyping yourself or the work by making extravagant claims: “This will earn millions of dollars!” or “The world has never seen a novel like this before!” Hyperbole makes agents and editors less eager to work with you.