Okay, so I almost always write in the first person, so things to consider are,
1.) What is your character's life like? Do they have family and friends? You may need to converse with them often.
2.) Become your character, as you are writing feel how you think your character would feel at this point in the story, this helps to put a lot more emotion in your story.
3.) Remember what you are supposed to sound like, if you talk sarcastically a lot, it's not a good idea to switch to emotional all the sudden with no reason
4.) Remember what you are supposed to like
5.) always check over your work, don't switch to third-person all of a sudden when you are supposed to be the character
6.) Don't be scared to have a lot of dialog, it helps the story go along
7.) practice, don't worry if your first draft doesn't turn out how you want it to, you will never get it right the first time, take your time and let the story grow
8.) Last and most important; HAVE FUN! writing doesn't have to be serious all of the time
I hope this helps, If you need anything else feel free to PM me.
~Logan
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