1. Read the guidelines! Be certain of what the publisher is looking for and how to submit it. If a publisher specializes in historical romances, don't send in your paranormal novel, no matter how good it is. If your book has over 100,000 words, but they take only shorter works, send your story elsewhere. If they require submissions through agents only and you don't have one, move on. There are plenty of publishers out there and you're sure to find a fit for your story.
2. Hook the reader with a great beginning. Often we start our "real" story several pages or even a full chapter after we've droned on and on to "set things up." Start off with that bang! Take a look at the first part of your story. Where does it start getting good? Start there! Put your character right in the middle of conflict and you've hooked the reader. Weave in bits of background later. Be sure to pace your story as well. You don't have to keep your characters in that constant state of stress. Give them, and the reader, time to catch their breath, but don't let things drag too long. Think of a story as a roller coaster ride with hills, valleys, twists and turns.
3. Heavily sprinkling a story with numerous adjectives and adverbs show that we writer's are there in the background making the story happen instead of allowing the reader to get lost in our characters and their unfolding drama. Look for strong nouns that say what you want them to say instead of using adverbs and adjectives as crutches to hold them up and make your point. That's not to say that they should all be omitted, but go through your story and see just how many are being used when a more simple sentence with strong nouns would get your point across.
Also, don't be afraid to say "said". Saying, "she articulated, he ranted, she whined, he uttered" just shows that we're trying to find another way to say "said" or to get the emotion of the character across. Using "said" is simple and gets your point across, but many times you don't have to add any tag at all if you SHOW what your character is experiencing or doing. Such as, "I've had it!" Mary threw the crystal vase across the room where it hit the wall and burst into a million tiny pieces. There's no reason to write, "I've had it!" Mary retorted angrily. We can see she's spitting mad by her actions!
4. Too much detail and narrative is another big problem--and one I was guilty of in my earlier days, and still can be to a point. Be sure to break up narrative passages with action and dialogue. Don't let the characters be inside their heads for too long or everything just stops. It's true that your characters have an internal life and a life before the story began, but it's best to weave in details here and there instead of boring the reader with long passages.
When giving background details, only include what's important at that moment. When a character enters a room, what does he/she first see? What's important or what sticks out? Describing a room or scene down to the last speck of dust has the reader turning pages to get to the action again. When we view rooms, scenery and people in reality, we don't make a mental note of every detail. We choose a few things that stand out to us.
5. Flat characters are another sure way to get that rejection. Be certain that your characters are people your readers will care about. The reader has to care about your character and what will happen to him/her or there's no reason for them to keep reading. Give your characters values, dreams, faults, quirks...make them real!
Be sure that your character's motivations are clear. The character must want something, but something or someone is preventing him/her from getting it. Your characters should literally take over the story as you write. Sit down and just watch what your characters do and relay that onto the computer. If we start manipulating them, forcing them to do something, the story loses its pacing and it ends up flopping on its face. Characters MUST have a compelling goal and conflict to keep the reader interested.
6. No plot to the plot, or using worn-out plots is another problem area. True there are only 20 basic plots, but use your voice and your ideas to breathe new life into them. Give your characters something they want desperately but can't have at the moment. How will they get what they want? Who or what stands in the way? How will your character get around it or through it? Editors and readers want characters with strong personalities, not wishy-washy wimps. And they want stories that have something new to say. Just because there are thousands, if not millions, of vampire novels out there, with your ideas and your voice you can add a uniqueness to it that makes it brand new.
My greatest method of moving the story along and creating a good plot? Ask yourself lots of questions and answer them. "What if a woman was lost in the middle of the jungle? How did she get there? Who is she? What is she after? Who's there with her? How will she get out?" By starting out with a simple two word question, you can generate a plethora of ideas for a novel!
7. Always read! Read what's being written out there in the world. Read for pleasure, but also read to learn. Whatever genre you're interested in writing, read as many books as you can that are in this line, especially if you enjoy the author's writing style. These people are in print and there's no reason you can't be too. As you read, make mental or physical notes of the characters, the pacing, the background details. What do you like? What could be better? I have a highlighter with me every time I read a book--provided it's my book! If there's a good line of dialogue, something that piques my interest, a good lesson in writing in detail, flashbacks, conflict, love scenes, you name it, I highlight it! This has offered me more inspiration and more guidance than any nonfiction book on "How to Write."
Although these tips won't keep you out of the rejection pile every time, by following them you have a much better chance at signing a contract than you do at adding yet another rejection to the pile.