Make sure you know who your target audience is, and cater to that.
For example: I don't know any boys who read The Fault in Our Stars or watched the movie BY CHOICE. If there are too many boyish elements in a book that primarily girls would be interested in, you're going to lose your target audience.
Write something original. This mainly applies to romance novels. Too many times we see the same story: the most popular guy in school is an idiot. The girl thinks he's hot. He suddenly falls in love her and they date. He cheats and she forgives her. Or, this one: He falls in love with her. He reveals to her that he has powers because her life is in danger because they're dating. She always wants to fight with him and he says no. If you're writing a romance novel, think: How can I make this not cliché? Of course, some cliché scenes are great. But if nothing about the plot is unique, not many young adults will be interested. When it comes to fantasy YA novels, try to think of the most original, never told before tale. All the bestsellers are very unique, in the sense that you'd NEVER think of that. I think this piece of advice doesn't just apply to YA novels.
Make sure your book starts off right. Most young adults have other things they could be doing other than reading. If they open your book and it starts off boring, most of the time, most of them will give it up almost immediately. And actually, I'm pretty sure most adults do this too.
Choose a topic that young adults will care about. This is probably the most important piece of advice. It doesn't matter how talented you are or how amazing the story is. If it's something teens don't care about, then no one will read it. And if you can't think of something a teen would care about, choose something that everyone will have to care about. An example of this could be a disease.
If you're struggling to find topics, read books by other successful YA authors. If you're thinking fantasy, find a fantasy YA novel. I recommend Cassandra Clare. If you're writing romance, I definitely recommend Meg Cabot. Sarah Dessen is another great one, too. This is a surefire way to find things that readers care about. And this will help if your publisher requests for you to suggest novels that are similar in tone to yours.
The others have said not to try to include teen jargon, which is very important. Don't even try. And if you ever consider it, read Sleeping Freshmen Never Lie. The whole time, the main character sounds like he's trying too hard, which is not what you want. However, make sure the teenagers ACTUALLY SOUND LIKE TEENAGERS. Too many YA novels have teenagers sounding like their whole vocabulary was taken from an SAT Vocabulary practice test. And make sure that even when your characters aren't speaking, make sure that your main character(s) has/have a teenager-ish tone, as readers will be able to relate better.
And always try to include a romantic element, as was already mentioned in previous posts.
And SARCASM. Teens LOVE sarcasm. Make sure to include it.
As you're writing the book, think about these questions in your mind:
WHO will read my book? What book has a similar audience, and how is mine different?
Has there been any idea quite like mine?
Am I relating well with my teen audience, or is it turning out to be more adult?
There are more, but my brain is tired. That's all I've got! Hope this helps!
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Make sure you know who your target audience is, and cater to that.
For example: I don't know any boys who read The Fault in Our Stars or watched the movie BY CHOICE. If there are too many boyish elements in a book that primarily girls would be interested in, you're going to lose your target audience.
Write something original. This mainly applies to romance novels. Too many times we see the same story: the most popular guy in school is an idiot. The girl thinks he's hot. He suddenly falls in love her and they date. He cheats and she forgives her. Or, this one: He falls in love with her. He reveals to her that he has powers because her life is in danger because they're dating. She always wants to fight with him and he says no. If you're writing a romance novel, think: How can I make this not cliché? Of course, some cliché scenes are great. But if nothing about the plot is unique, not many young adults will be interested. When it comes to fantasy YA novels, try to think of the most original, never told before tale. All the bestsellers are very unique, in the sense that you'd NEVER think of that. I think this piece of advice doesn't just apply to YA novels.
Make sure your book starts off right. Most young adults have other things they could be doing other than reading. If they open your book and it starts off boring, most of the time, most of them will give it up almost immediately. And actually, I'm pretty sure most adults do this too.
Choose a topic that young adults will care about. This is probably the most important piece of advice. It doesn't matter how talented you are or how amazing the story is. If it's something teens don't care about, then no one will read it. And if you can't think of something a teen would care about, choose something that everyone will have to care about. An example of this could be a disease.
If you're struggling to find topics, read books by other successful YA authors. If you're thinking fantasy, find a fantasy YA novel. I recommend Cassandra Clare. If you're writing romance, I definitely recommend Meg Cabot. Sarah Dessen is another great one, too. This is a surefire way to find things that readers care about. And this will help if your publisher requests for you to suggest novels that are similar in tone to yours.
The others have said not to try to include teen jargon, which is very important. Don't even try. And if you ever consider it, read Sleeping Freshmen Never Lie. The whole time, the main character sounds like he's trying too hard, which is not what you want. However, make sure the teenagers ACTUALLY SOUND LIKE TEENAGERS. Too many YA novels have teenagers sounding like their whole vocabulary was taken from an SAT Vocabulary practice test. And make sure that even when your characters aren't speaking, make sure that your main character(s) has/have a teenager-ish tone, as readers will be able to relate better.
And always try to include a romantic element, as was already mentioned in previous posts.
And SARCASM. Teens LOVE sarcasm. Make sure to include it.
As you're writing the book, think about these questions in your mind:
WHO will read my book? What book has a similar audience, and how is mine different?
Has there been any idea quite like mine?
Am I relating well with my teen audience, or is it turning out to be more adult?
There are more, but my brain is tired. That's all I've got! Hope this helps!