1. Too many adverbs
Overuse of adverbs will scream amateur louder than anything else. Many creative writing tutors say any use at all is overuse.
In case you don't know, adverbs are words that modify a verb to describe the way the action is done. If you don't know what modify means, you should probably consider switching to photography. Adverbs often end in 'ly'.
He said, knowingly.
She dropped the knife, meaningfully.
The problem with adverbs is that they are often redundant, re-stating something that is obvious from the dialogue or verb. And if it's not obvious in the dialogue or verb - why isn't it?
Adverbs are also a key indicator for weak verbs. You can think of the ly as a crutch.
He walked weakly to the door
Might be replaced by:
He stumbled to the door
Adverbs are often a marker of lazy description, and showing, not telling
(see next mistake).
2. Telling not showing
If you haven't heard this yet, brace yourself. You'll be sick of it within months. It's very common for new writers to try to explain things to their readers, as a kind of omnipotent narrator, rather than allowing the reader to experience everything themselves through the protagonist's senses.
For example, if you tell me that:
Martin Cousins was furious and so he went into the shed to calm down.
I'll be yawning before you get to the next sentence. So what? And anyway, so you say.
However, if you say that:
Martin slammed the back door and stormed down to the shed. He punched the wooden door aside and kicked it shut behind him. He waited in the darkness, forcing himself to take a few slow, deep breaths as the dust settled.
Here the point is made vividly and at no point did you need to be told Martin was angry. You can feel it. We can observe the cold, hard facts with our own eyes.
3. Overly formal dialogue
The main problem with natural dialogue in fiction is that it's nothing like natural dialogue in real life. If an author did put genuinely genuine sounding dialogue into their work, readers would be bored silly, because normal speech is full of half finished sentences, interruption, meandering and assumed knowledge.
So fictional dialogue needs to be much more succinct, with clear direction and eloquence, but to still give the impression of being natural.
One tip to make speech sound less formal is to use fillers (well, umm, I guess), pauses, interruptions and contractions (do not = don't, I will = I'll).
4. As you know, Bob
This is the common phenomena of writers using a character to explain a plot point to another character who already knows it.
To take an unlikely example - let's say knowing the ingredients of the common Screwdriver cocktail is critical to the story. The amateur writer might decide to have two barmen, one of whom says something along the lines of:
'Well, as you know Nick, a screwdriver is a mix of vodka and orange juice.'
Clearly, Nick already knows it. Why is his colleague telling him something so obvious? This just doesn't ring true, and your characters are suddenly mannequins dancing to your plot rather than real people the reader cares about. It's just a sneaky way of telling (see above).
Characters should never say anything that the person they're talking to obviously knows already. This isn't to say a character can never explain a plot point, just make sure they are telling it to someone who genuinely wants and needs to know.
5. Lack of Conflict
Put simply, if there's no conflict, there's no story, and by conflict, we don't mean violence. Take these two alternatives:
Boy meets girl, they fall in love and live happily ever after.
Boys meets girl, girl despises boy, girl gets a terminal illness, boy searches the world for a cure to save girl and win her love.
If you could ask a single question about either of these premises, what would it be?
Would it be 'In number one, what precise way did they live happily ever after?' or would it be 'In number two, does the boy find a cure of not?'
Knock me down with a feather if I'm wrong, but I'm guessing it's going to be the second, which means you're engaged and intrigued. That's because there's conflict.
Lots of people decide to write based on actual experiences because they realise that real life is stranger and infinitely more fascinating and complex than anything a single human mind could dream up. This is all well and good.
What is not well and good, is thinking that your life is interesting enough to be committed to paper and inflicted upon innocent readers. Unless your life has involved bringing down a massive corporation, starting a revolution, overcoming a debilitating disability to spectacular effect or saving a boatload of people - it's unlikely to be interesting enough to be worthy of novelisation.
The same kind of principle applies to peppering your work with your opinion.
As the great William Strunk, Jr. says:
'To air one's views gratuitously, is to imply that the demand for them is brisk.'
This is a big one. In fact, if you're reading this, there's a good chance you're procrastinating now.
Procrastination is a huge enemy to success, as you can hardly get to the exciting stage of having your novel rejected if you haven't even written it yet.
Ultimately, the only answer to procrastination is will power and inner strength - however, there are plenty of tips and tricks to help overcome it.
Two favourite 'reasons' and answers:
'I'm not inspired' - If you want to be a writer, it's your job to be inspired. If you have to sit around staring at the wall, waiting for the muse to belly dance in front of your nose, you'll starve long before your first draft is even begun.
'I don't know how to get started' - Make and follow a plan (such as the Snowflake method) which has small, achievable goals.
Further reading (not without irony):
8. Meandering Plot
Stories need to go somewhere. Unless you're CS Lewis, you're unlikely to be able to get away with having your character randomly wandering around an abstract world, encountering characters that apparently have no relation to each other.
Your protagonist needs to have a goal, and while that can change over time, there needs to be some consistency. Your reader wants to root for your characters and feel clever if they guess what's coming. If you randomly change direction and the first five chapters describe a man trying to clear his wife's name when she's accused of murder, but then by chapter seven he's trekking through the rainforest and the story ends with him bringing down a terrorist plot, your readers are going to feel cheated. And headachy.