What I like to do with my OCs is I try to give them the correct attire for where they live. Like, if one of my OCs lived in a colder climate, I'd most likely give them a jacket or a sweater. Or if they lived in a warmer climate i'd give them shorts, a tank top, ect. You get it. This isn't really necessary, but in my opinion it'd be weird if your OC lived in Greenland and wore a miniskirt. (Unless they were really dedicated)
It's also important for your clothes to match your characters personality. I don't mean it in the way where they can't be bitter and wear pastel clothes. I just mean it in the way if your character was a skank they probably wouldn't dress modestly. It's important for you to express your OCs personality, not only in speech, but in clothing styles, hobbies, favorite colors, ect. Even if those expressions are subtle.
Also, like in appearance, avoid neon colors.
