How I Develop Characters From Scratch

My characters always start as one-dimensional. I usually see a scene from the book in my head with very little background, and then I ask myself why. To illustrate this, I’ll use my book, Unwrap My Heart, as an example.
Pro tip: this method is amazing for co-authors, and I in no way answered these questions by myself. We both had control of our characters and had to work on the puzzle together. However, I do this for my solo books as well, so it should work regardless of the book you’re writing or how you’re writing it.
I wanted to release a short story for Christmas and got my friend on board to write it with me. I didn’t have any characters in mind. I just knew I wanted it to be a young adult romance. We got on the phone and began pitching ideas for the conflict.
What if she’s just been through a breakup, then meets a new guy who sweeps her off her feet?
Internal conflict is good, but that doesn’t give a lot of direction for the external plot.
What if she’s homeless, and the guy takes her in?
Now we have the inciting incident for the romance and a reason for her to resist it. How can she trust anyone when everyone she did has abandoned her? And she can’t get comfortable with the living situation because it’s temporary, and the guy’s parents could kick her out if they discover her living in their attic.
What if her ex-boyfriend is new guy’s best friend?
Now he has a reason to resist romantic feelings, and she wouldn’t want to hurt her ex by dating his best friend.
As you can see, the external and internal conflicts necessary for an outstanding book also inform who the characters are. But for there to be character growth, it’s important to know where the characters have been and where you want them to wind up.
The wind-up part is simple. It should mirror where they began. So, in the beginning, my character is homeless, without a support system, and brokenhearted. By the end, she’s found a stable place to live, has a support system and is in love.
We already established what the conflicts in the story are, so to find the beginning of the story, turn each of those into why questions.
Why is the new guy interested in her if he’d feel bad about betraying his best friend?
He had a crush on her first, and his friend was never a great boyfriend to her.
Why didn’t he ask her out when he had the chance?
He was already dating someone.
Why didn’t he breakup with her?
Because she had recently lost her mom, and he didn’t want to make her life worse.
Why is the main character homeless?
Because she got kicked out.
Why did she get kicked out?
She aged out of foster care.
Why didn’t she plan for that?
Because they told her she could stay.
Why did they change their minds?
Because she threatened her foster dad.
Why did she threaten him?
By the time you answer all the why’s, you’ll have a fully formed character and an exciting storyline. Playing the why game is so much more beneficial than any character profile sheet because everything you discover will go into the book. There’s no wasted time. There’s no second-guessing. And no matter how wild the story is, it’ll be believable because you’ve answered all the questions the reader will have. Suspension of disbelief is unnecessary because you are a rock star character creator.
In summary, start with a list of conflicts relevant to the genre and subgenre you want to write. Then play the why game. I guarantee you’ll come up with something amazing. When you do, come back here and let me know how it went.