This bit of characterization mainly applies to Coraline. Coraline's clothing becomes a reflection of her personality. She wants her mom to buy her bright green gloves and she shows an interest in galoshes that look like animals; this helps us see that she's quirky and fun. Coraline's mom only buys her boring school uniform clothes though: if Coraline's clothes represent her personality, then Coraline's mom is kind of trying to squelch her daughter's awesomeness. What gives?
Because Coraline doesn't have a lot of people to talk to, actions speak louder than words in this book. The other mother may say nice things (like "[y]ou know that I love you" [9.7]), but it's really all a sham: as we know, she's totally evil and crazy. We probably get our best sense of the other mother when her hand is scuttling around Coraline's house. The hand can't say anything, so we only have its weird and evil actions – namely, trying to steal the key – to go by. The other adults in the novel are also largely characterized by their actions: the politeness of Misses Spink and Forcible, the distraction of Coraline's parents, the odd habits of Mr. Bobo. What people do really defines them here, often more than what they say.
Food becomes a key point of difference between the two worlds. In the real world, Coraline is never overly thrilled with the food her parents fix. She always wants something different: they don't even have the things she likes in the house (like the awesome Limeade soda she drinks at Miss Spink and Miss Forcible's house). In the other world, the food is really good. Actually, it's too good to be true. Coraline might wish she could eat herself into a food coma, but she also knows that the other mother is using delicious food to distract her from going home. Here, food is used to characterize the other world: it's boring in the real world and enticing in the other world. But sometimes we have to settle for Dad's recipes if it means living in reality.
Physical appearances really distinguish the two worlds from one another; not only the appearance of the worlds themselves, but also of the people in them. Pretty much every character has an alternate in the other world, and there are major differences in how each version of a character looks. Let's see: the other mother is taller and thinner than her real mom and has majorly crazy fingers and fingernails. Miss Spink and Miss Forcible are young and beautiful. Mr. Bobo is, you know, made out of rats. These appearances characterize the "other" versions of the characters as, well, creepy. And because of this, Coraline is able to see that this isn't the place to be.