Characterization is SO important in your story. Unlike real life, a character should have reasons for their actions and their actions should line up with their personality. Slobs don't have neat bedrooms. Perfectionists won't throw their Burger King bag on the floor of their car. So when you write a scene, make sure the character is doing things consistent with their personality.
That goes for dialogue, too. Someone raised in Alabama will speak differently than a New Yorker. Not just in dialogue, but maybe in the way they view life. If your hero was raised tough, have him talk tough. Be consistent.
I always thought I was consistent. Until I won an editorial review.
Very few comments in the chapter, yet one was next to a paragraph of the hero. The editor wrote "inconsistent characterization". You could have knocked me over. I never saw it coming but it really turned on a light for me.
Now when I write I always wonder, would she do this? Would she say this? And would she really compare her attraction to the hero to what she feels for her toolbox?
Only if she's into tools.
This characterization thing can get fun, once you get the hang of it. For example, in one of my manuscripts the hero is a government agent in covert ops. This is back in the day, with the beginnings of the FBI. For fun, I had him inwardly compare the heroine's eyes as "shining like the stock of his favorite rifle". Well, not exactly like that, but close.
It still makes me laugh. Whenever it gets critiqued, if it's jarring, I'll take it out. But for now it's a part of his characterization, because he thinks in terms like that.
Whew, long post, huh?
So what's your favorite characterization tools? How do you decide what to use and what not?