When you are writing a novel, unless your story is autobiographical, you are usually going to have to do some research. This can even be the case when writing in fantasy settings, because you’re still going to need to establish things like the roles your characters play in society and how that society works (consider things like in world economies). When you are writing something with a real world, contemporary setting, research will usually be about things that factor into your story, such as legal protocols if you are writing a mystery, or things that will add realism, such as the make and model of your protagonist’s car.
Jobs can be a big part of this, but how much do you actually need to know about a job to be able to write a character who does it?
One thing you will definitely want to know is how much money your character would make doing their job, because you may need to put in other things that help support other elements of your story to make them believable. The girl who works in a book shop in your romance novel probably wouldn’t have the income to also live in a quaint Victorian townhouse, so you may want to give her a roommate, or have her inherit the house. Equally you might have given your character a high-income job, so you’ll need to consider why he is in debt to the mob. You can find out average salaries for a lot of jobs at Quality Education and Jobs.
Most people don’t expect or want too much technical detail about someone’s job unless it is an important part of the story, but their lifestyle in terms of their working pattern and stress level has to ring true. If you are writing about a high school teacher, you can’t really have them going on trips out of town at short notice during school term time without an explanation. If you are writing about an ER nurse, they probably don’t have a 9-5 schedule. While you may not need to know much about physics to write a character who is a physicist, you probably want to know how research projects are funded and how scientists are judged on what they achieve. Then there are career paths. How long into a promising lawyer’s career would they be trying to make partner at their firm?
Don’t Gloss Over the Job
Sometimes, the job your character does isn’t important to the story at all – you just need them to have one or to have the means to make the income you need them to have for other reasons. This can fall flat however if you don’t reference their work at all. If your character is a CEO just because you need him to be rich, sure, you don’t need to research how he might diversify his investment portfolio, but you should probably not have him spend every scene doing non work related stuff and never mentioning his company, either – a real CEO would treat their business as one of the biggest priorities in their life, and so it will seem like bad writing if he appears to be as interested in his work as the average pizza delivery guy.
Researching jobs doesn’t mean you need to, by the end of it, practically know how to do the job yourself unless the job is a major feature of the work, but there should always feel like there is an authenticity to a character’s lifestyle, and that you haven’t just given them an unusual or interesting job you’re never going to actually talk about in the book for the sake of it.