It’s the substance and not so much one measly typo that will attract an editor’s eye, but bear in mind, that an editor notices both. Having read thousands of submissions, I can spot the writer who really takes her/his work seriously. She’s the one who obeys basic rules of grammar and proofreads her work. I’ve heard at conferences, “Well, the editor will fix all my typos.” Sure, but handing in sloppy work will guarantee a rejection.
Here are the three mistakes I see most often:
1. Lack of comma with direct address: This one really confounds me, especially since it’s a common mistake made by educated people. Thanks for the strudel Dave. You’re welcome Marcy. Arggggh! Make sure you put in those commas so that I don’t think there’s a strudel named Dave. Example: Thanks for the strudel, Dave.
2. You’re or your: With Twitter, Facebook and texting demanding a fast turn-around time, it’s easier to confuse “you’re” and “your.” Remember that “you’re” is the contraction for “you are.” “Your” denotes possession. Example: You’re awesome! Your dog just ate my flowers.
3. Typos: Spell check isn’t enough. You have to read through your entire manuscript and not just look for the red and blue lines. Read carefully. Then, get a friend to read it. After this, you should read it again and then hand in to an editor.
The bottom line: If you’re a writer, become a fan of grammar. It will show you as a professional rather than an amateur.