Really, really, really read books on craft to give yourself good blueprints and so you can write well and recognize quality from trash.
And even if your work IS cutting it, there are some jewels you should always include to make sure it goes from workable to downright awesome.
1. Good flow
Create good flow, pace and rhythm not just in the plot but in your narrative, the way things unfold, the way sentences and paragraphs connect.
This means varying your sentence length, starting with a gerund every now and then, mixing things up, avoiding crutch words or awkward turns of phrase, not having every sentence start with He/She/Sue. You don't want to have a choppy read nor do you want to one that forces readers to struggle through shattered and plentiful ten-line sentences.
Avoid dumps of description and backstory. Even if you're writing omniscience and can do it seamlessly and the point-of-view character is super observant and truly notices everything you point out, don't go overboard. Consider those details to be ribbons, sequins, accessories. They should dress up your work, not make up the bulk of it. If readers are tugged into a quagmire of verbage, no matter how great it sounds to you, you risk losing them somewhere in Ch. 6.
In my novel, Kings & Queens, I made the mistake of including a few paragraphs of backstory on my character Derek when I opened his POV, but that clashed with my close perspective. I slashed all that and took it down to a line or two, as it applies to his thoughts in the scene.
Sometimes we get caught up in wanting to include everything, and too much info can be overwhelming and annoying. Think of your prose as music. Only important details are needed in that score.
When you think you're all polished and ready to shop, email yourself the first couple of chapters and random sections. It sounds weird I know, but reading scenes out of your text document will help you notice issues with pace and rhythm especially. I noticed some choppiness and sludgy spots in my chapter 1 this way, which is the first thing agents see. Now I'm good to go.
2. Unforgettable Characters
It sounds obvious. Every wants unforgettable characters, but as a reader, how many times have you read a great book, then a month or too later, can't recall names? Then you have to skip over to Amazon to check 'cause the not knowing is bugging the snot out of you.
I have photographic memory, and this happens to me. A lot. Even if I loved a story and the characters in it.
Don't' let readers experience amnesia. Let your characters jump off the page and demand to be noticed and not quickly forgotten. Develop your characters so that they're nearly palpable, then tether aspects of plot to their identity and desires. Give an extraordinary quality or interest that's rarely seen and this will create the memory stickiness you hope to achieve.
3. Fresh Voice
Your voice is in everything you write from tweets to novels. Be inspired, but don't emulate the style and voice of others. Let your own uniqueness emerge. Voice is an expression of the weird way your mind works, your personality in written word, your take on things, your way of speaking. Even this post has voice.
It should flow out naturally. Even if you write with different tones or various quirky First Person narrators, a bit of you should still shine through. If you're feeling unsure or self-conscious, it will be noticeable. The only way you can gain confidence and to find YOUR voice is to practice.
People have called my writing quirky and different. I love giving readers golden nuggets of my weirdness. It puts a branding on my own works.
4. Balance in The Force
Your work can be packed with darkness, conflict and obstacles aplenty, but it should have some kind of forward momentum. In darker works, add some ribbons of dark or dry humor, irony, hyperbole, romance, tone shifts, brief moments of peace, lightness and success. This will bring more scope and needed contrast into your work.
Also, if your work is lighthearted, you should have present or brewing trouble, a paperboy who wants his two dollars, office cat fights (they happen!), insomnia, a stalker, a death in the family, skeletons in the closet, the annoyance of every Starbucks within twenty miles being out of whipped cream so there's no way to gloriously top off that Java Chip Frapp.
Always think about balance and contrast. My novel, Kings & Queens, deals with violence and psychological terror, but it still has bits of humor and scenes that tug at the heart.
So, I've given you some direction towards making your work shine. Go write and make your work AWESOME.
~ Signing off and sending out cyber hugs.