1. Beginning every sentence with 'I'

The first-person narrator tempts writers into focusing on the narrating character to the exclusion of other subjective nouns. The result is a stultifying string of sentences that all feature the same subject. Mix and match subjects to electrify some life into your syntax.

I went to the park. I saw a big duck. I loved watching all the people. I thought of how the clouds looked like anvils.

Tired yet?

Please don't start every sentence with "I." It feels quite redundant.

Create sentences that have an implied"I", or talk about things other than the narrator.

Of course, don't go to the opposite side of the spectrum and try to avoid "I" completely. After all, it is the most important word when writing first person.

Example ----

Wrong: I fled down the stairs, heart pounding. I could hear the zombified giant clomping after me. Ahead, I could see the cellar door offering me the chance to escape and hide. I reached the door, wrenched it open, and dove inside.

Right: My heart pounded as I fled down the stairs. Behind me, the zombified giant clomped after me. Five feet ahead, the cellar door offered the chance to escape and hide. I reached the door, wrenched it open, and dove inside.

2. Telling thoughts instead of showing

In the first-person narrative, everything you write is straight out of the main character's brain. You don't need to clarify the character's thoughts by placing them in italics or qualifying them with an "I thought" tag.
Example ----

Wrong: I couldn't believe this was happening. Zombified giants don't really exist, do they? I thought to myself. Maybe I'm dreaming.

Right: This couldn't be happening. Zombified giants didn't really exist, did they? Maybe I was dreaming.

3. Inserting lengthy narrative at the expense of action and dialogue.

First-person narration offers the temptation to share with readers everything the character is thinking. But beware of lengthy narrative rabbit trails when you should be allowing action and dialogue to carry the story.

Example ----

Wrong: "What's up with you lately?" Kirsten asked.
I heaved a sigh. Kirsten had no idea how insane my life had become. She had no idea that zombified giants-huge and ugly and stinky-were after me. [Insert lengthy description of zombified giants, narrator's life, history of friendship with Kirsten, etc.]

Right: "What's up with you lately?" Kirsten asked.
I heaved a sigh. "You have no idea how insane my life has become." I threw my backpack into my locker, shot a surreptitious glance up and down the hallway, then leaned forward to whisper in her ear, "Zombies! Big ones!" [Insert witty, conflict-ridden dialogue that conveys the important information about zombified giants, narrator's life, history of friendship with Kirsten, etc.]

Utilizing a first-person narrator can be an exciting way to create an immediate and intimate story readers won't be able to turn away from. Make sure you aren't stumbling over these common mistakes, and you'll be more than ready to knock readers (and maybe some zombified giants as well) off their feet with your powerful narrative.

4. Reader is Trapped with One Character

By reading a first person book, your reader is essentially in an elevator with your narrator for six or eight hours. Don't make it the most miserable elevator ride of their life.

First person characters have to have some redeemable characteristics, or else they'll just be hated by a reader. Even if they have terrible faults, make them interesting faults. Alcoholism, for instance, is overused as a character fault of protagonists, especially in the hardboiled genres of detective and mystery stories. Don't give your character cliched faults.

5. Make Sure Your Character Isn't Just Yourself

The most important thing to remember when you're writing first person is that you're not yourself. Scrape away your personal voice and replace it with another person's voice, a person you've created. It's probably going to be some small part of you, but it's not identical to you.

First person is the closest writers get to actors. You're essentially acting when you're writing first person. You're pretending to be another human being, mimicking their every thought and expression and word. So feel free to invent someone!

6. Avoid Filter Words

There are some great articles out there on avoiding filter words.

Essentially, you don't write:

I looked at the horde of political protestors racing down the street.

You write:

The horde of political protestors raced down the street.

Just cut out the action of your first person narrator looking, seeing, and acting. It'll make the prose much more direct.

7. Difficulty of Limited POV

Sometimes writing first person can be tricky when the reader needs to know about something happening in another storyline, or in another part of the world.

But this voluntary obstruction that the writer elects to take upon himself will eventually strength the story. It's counter-intuitive, but if you make up obstacles for yourself, you're going to force yourself to be more creative.

So don't look at the limited first person POV as a hinderance but rather as an opportunity or a challenge.

*****

I hope it will help you.