That which is outside your understanding is essentially invisible to you. If you do not understand grammar and punctuation, you cannot fix it in your own writing.
To improve your writing, you must learn to spot errors on a multitude of levels. The lowest of these is the level of the sentence, of base grammar and punctuation.
When you've mastered the mechanics of grammar, punctuation, sentence construction, and its variations, you can start worrying about higher-level, more abstract problems in a story--things like narrative structure, rhetorical strategy, image painting, and a whole host of other concerns.
Here's how I sharpened my skills:
I had my first professional writing job at age 18, when I worked for the Port of Los Angeles as an assistant to the Port's Public Relations Director. I beat out the other candidates by pitching my writing skill. The interview actually included writing an on-the-spot press release, given only a few bullet-point facts about a fictional shipping incident.
I wrote every press release that came out of there during my employment with the Port, though under my boss's byline. I enjoyed it a great deal, even when I was working 20 files at once with myriad deadlines.
I still remember, to my shame, my boss chiding me for accidentally writing "it's" where "its" was called for. I never made that mistake again thereafter, and I hungered for much deeper mastery of written language.
A professional writer cannot afford to make such mistakes and often has no one to catch mistakes. Especially for short stories and novels where editors and agents are looking for reasons to discard your submission; a grammar or punctuation mistake can be an instant ticket to the garbage bin.
I recently critiqued a short-story on Critters.org which was rife with incorrectly used colons, semi-colons, and commas. Worse, they were all over the place, used far too often. I'm talking like one per paragraph instead of maybe one or two per story. These punctuations are to be used like spice--too much spoils the soup. Seek balance and err on the side of not using them.
It doesn't matter how good your story is if you cannot properly punctuate it. That would be like, say, trying to rebuild an engine without knowing the proper type of grease to use in the bearings, or using it in the wrong places.
My first strategy for improving myself to a professional level was to take a full-on course in traditional syntax. And that meant I'd be doing a lot of something that I was actually looking forward to: sentence diagramming.
For a long time I savored the thought of performing sentence diagramming. Hard to believe, I know. Diagramming a sentence is equivalent to popping the hood of a car and learning what the individual parts do. Most people don't know and don't want to know what's going on in there. That's fine, but I must know.
The kind of familiarity with the flesh and bones of a sentence that sentence diagramming gives you is what I was after, minute attention to detail and mechanics, and this class delivered.
The text was this one: Doing Grammar: Fourth Edition
by Max Morenberg.
It was a fantastic learning experience. I never had the opportunity to do sentence diagramming as a child because the practice had already been banished from elementary schools by the time I got there.
This book uses a diagramming method that is slightly different than the traditional under-line method, and I think it's better. It has you drawing logical-connecting lines above a sentence and labeled, with the benefit being that you don't need to reposition the words at all, yet the connections are seen and understood easily.
Today, there's a resurgence of teaching diagramming, and I think it's a valuable tool that I wish I had learned from while young.
Apart from that book, there's a website that I've used lately to brush up on a few nagging habitual errors and to deepen my attention to the subtleties and vagaries of punctuation. It's among the best sites on grammar and punctuation I've found so far because not only is it completely free, it's also interactive.
It's called ChompChomp.com, titled "Grammar Bytes", written by Robin L. Simmons.
Its pages are spare, making it easy to find exactly what you're looking for. The interactive tests are separated into categories of what you want to brush-up on, and are well designed, though perhaps overly encouraging to a humorous degree when you do get one question right. You'll see.
I was recently talking to a friend from class who also wants to write professionally. She told me that she was constantly getting dinged on her class essays for grammar and punctuation mistakes. Professors tend to use mechanical mistakes as an "objective" test of writing skill, in the grading rubric. At least when it comes to knocking off points.
I can't remember the last time I was dinged for any major basic errors like that. I mean, I once accidentally indented the right margin of the entire paper after a block quote, heh. Didn't lose points for that though.
It's almost like cheating, because my essays get a boost compared to other students by simply being mechanically excellent. Not that I'm complaining.
Next semester I'm taking an upper-division creative writing course. I've got several short stories just waiting to be written, with nearly complete plots. They've been stewing for many months now. I can hardly wait.
So, if you need work on grammar and punctuation, put in the time and effort to really learn the craft of writing. You need discipline, ideas, and talent, sure, but you must pay your dues and put in work on the basics. Even if you're better than average compared to your peers, that still probably does not meet the professional standard.
Master the basics before moving up to the strategy of fiction and narrative structure, create a solid foundation for your writing to rest on and you have a chance at success. Continue to struggle with grammar and punctuation and success will elude you forever.
