This is such a great topic and I hope more Sim writer's stop by. I also have a Sim writing tip I would like to share as it just may help someone out there. My tip expands upon this point:
Delve into the minds of your sims; not just the ones you create but the ones EA have left for your created sims to interact with. What are their motivations. What is the background that brought them to that point in life? Flesh out all your characters. What are their motivations - what drives them to be that way?
@Nikkei_Simmer - Oh, Jared ain't so bad. He's a lot better than that Xander Clavell (the one Sim I don't like). ;)
My Tip:
Learn about your Sim Subject, even those which you have created and then spin and/or expand upon that knowledge.While I agree, fleshing out your Sims personality and lifestyle does make for a better story. Understanding what makes a Sim tick, in my opinion, is more easily done when the characters are your own (as in created by you). Because at this point you are the only one who knows them and their path, the reader will learn about them through the telling of their (your) story.
However, when it comes to writing stories about pre-made Sims, these are Sims who everyone who plays the game knows a little bit about and/or has some experience with. This doesn't mean their roles can't be re-written by the writer, they so totally can! The trick is in how to transition them from who they are into who you want them to be (in your story) while still remaining true to the character (Sim). So, in my opinion it is best to learn a bit of history about those Sims to better understand your subject first.
Keeping with the Jared Frio example as set forth. If you want to know what motivates Jared just read his brother Connor's bio.
"A loner by nature, about the only person that Connor Frio doesn't mind having around is his brother, Jared. After all, his brother leaves him alone to be his own person, never trying to push him or mold him the way his parents and classmates did. No, Jared doesn't mind that Connor often likes to just sit alone, reading a good book, so why would Connor want to spend time with anyone else?"
From Connor's bio you learn the Frio brothers grew up in a two-parent demanding household. It is clear from the description their parents had
'expectations' of their boys and were a bit forceful about expressing those expectations. Knowing this gives you a bit of insight into Jared's bio:
"Jared Frio isn't sure what he wants to do with his life. He knows he's good at cooking, but he just doesn't have the drive or ambition to become a great chef. He knows he's good at charming people, but he just doesn't have the desire to do more than scratch the surface of relationships. What will it take to aim him in the right direction?"Jared's developed 'meanness' (rebellious nature) most likely comes from two points of motivation in his upbringing. The first is fighting against his parents dominating wants for his life and the second is protecting his younger brother's individuality from the forced desires of their parents (and possibly others). As far as his thoughts of self goes, he desires to become his own Sim. He knows a little bit about himself but not enough to make a dedicated decision about his life or future path. And, he will not be forced into one.
From this Jared's trait choices begin to make sense as does his behaviors. Natural Cook, Heavy Sleeper, Mean Spirited, Inappropriate, Party Animal.
Jared is the elder brother of Connor and the stronger of the two. He can take a lot of negativity and give back as good as he gets. He has had years of practice standing his ground against his parents and others. It's not so much that Jared is 'Mean', he just strongly objects to being forced into anything which he isn't certain about, this includes his relationship with Claire.
In a way, Jared's 'inappropriate meanness' is nothing more than a coping and defense mechanism when faced with authority (or the likes). According to EA, Jared finds stress relief when he is in the kitchen cooking, sleeping or partying. Now that you have a basic understanding of Jared, use what you have learned to guide his life and change his story into whatever you want it to be.
And by all means, just have fun creating and writing!