First things first, if you just want a quick fix that will help you keep all of your characters’ motivations and journeys in one place, here’s what you do:
- Get a bunch of sticky notes or index cards
- One each note-card, write down:
- a character’s name
- their main goal
- the action they want to take/will take to achieve that goal
- and the outcome
Simple and straightforward. And 90-99% of writers already know they should do this. But don’t forget that this doesn’t just apply to your protagonist and antagonist. Give your side-kick, love-interest, mentor, etc. a motivation independent of the main character’s motivation, and it will give your story depth.
It can be easy to fall into the trap of having the world revolve around your protagonist–especially if you’re writing the story from their perspective. Even if your protagonist is oblivious to other people’s motivations, each individual character does have a reason they’re doing what they do. And just because your narrator doesn’t know what those reasons are doesn’t mean you, the author, are equally oblivious.
How do I know which characters need an arc?
A good indicator is if you’ve named them. Whether you’ve consciously done this or not, naming a character often indicates to the reader that this character is important. Not every named character needs an arc, but every character who has an arc definitely has a name.
Another indicator is how many times they show up in your story. Are they in one scene and never show up again? You can probably leave them be (unless they’re going to show up in a sequel).
Are they in three or more scenes? Do they have a speaking role? Do they help/hinder your protagonist at any point in the story? Do they have a role in the climactic scene? These are the characters whose motivation you should be consciously aware of.
What kind of motivations should my side-characters have?
The possibilities are endless. Revenge, greed, selflessness, a desire to protect the ones that they love, survival instinct, peer acceptance. I could go on and on about the different things that motivate people. Here is a good starter article on basic human motivations, in case you need some inspiration.
Keep in mind, however, that your character’s motivation and arc need to somehow connect to the plot. Let’s use Pride and Prejudice as an example. Jane Bennet is not the main character, but her romantic subplot with Mr. Bingley directly affects the protagonist’s relationship with her own love interest (Elizabeth and Mr. Darcy). The same is true of Lydia Bennet, who, by eloping with Mr. Wickham, helped reveal the truth of Mr. Wickham’s character and gave Mr. Darcy the opportunity to redeem himself to the Bennet family (by paying for Lydia and Wickham’s wedding).
The point is that your side characters must have their own journeys and their own desires, but they should not be completely arbitrary. If Jane and Mr. Bingley’s relationship had absolutely nothing to do with Elizabeth and Darcy’s relationship, then what would be the point of including it? If Lydia had gone on holiday and run off with another soldier instead of Mr. Wickham, Darcy’s kindness in paying for their wedding wouldn’t have had the same impact–if he’d have even done so in the first place.
In Short: give them a goal that is not exactly the same as the protagonist’s, have them act on their goal, and make sure their motivations stay relevant to the overall plot. (If you cannot seem to make the side-character’s journey relevant, it may be time to consider cutting them out all together.)