Hint 3: Make Their Job At Least A Little Bit Exciting
One of the most common mistakes that rookie screenwriters make is giving their characters a non-visually compelling, conflict free line of work. This is a problem, because most adults spend a large portion of their time at their jobs, meaning that, at some point, we’re going to (most likely) have to see your character at work. If your character has a boring job, it is going to make the character themselves look boring, and your audience is going to stop caring, which is the kiss of death for a screenplay and, by proxy, a film.
You want to, instead, give your character a profession that demonstrates the following qualities in spades:
Lots and lots of visual conflict
A high amount of emotional tension and high stakes
A large amount of obstacles for them to overcome – no one wants to watch a hero stuff boxes all day
Any sort of regulatory system or government that makes things more complicated for the protagonist
A ton of problems, in any form, no matter where they come from
This doesn’t necessarily have to be a legal job, nor does it mean the character has to be directly compensated for it – in this case, a job has to do with responsibility, not the dollar amount that the character is being paid for it. As long as it generates a palpable tension that the audience can get invested in, that’s what is important.