Character Clues
Character Analysis
Actions
People's actions when left to their own devices (especially in times of war and survival) really say a lot about their characters. Piper, for example "always throws the fish back" (1.5.6), while Edmond does things like turn "the car up onto this grass and then drives across to a sign that says Do Not Enter and of course he Enters" (1.2.11). It doesn't take a rocket scientist to gather from their actions that Piper is a gentle, sweet soul who can't stand to cause other living beings pain, and Edmond is somewhat a of a rebel rule-breaker.
This is true throughout, so pay attention to what characters do—especially since the only character whose thoughts we have access to is Daisy.
Direct Characterization
Daisy's blunt, and she frequently tells us exactly who everyone is and what they're like without beating around the bush much. She'll even go as far as to say things like, "I'm thinking now would be a good time to talk about Isaac" (1.8.1), setting us up for her no-holds barred assessments.
From Daisy's descriptions we know without having to piece anything together that "Piper and the sweet baby goat were exactly as nice as each other" (1.4.12), that Osbert was "always pushing himself into the conversation with superior information" (1.8.3), and that "Edmond on the other hand was totally up-front" (1.8.4). Just like that, we've got ourselves a decent grasp on the cousin crew.
Daisy's direct descriptions make it clear to the reader that Isaac's a silent caretaker, Piper's the sweet, innocent one, Osbert's the know-it-all, and Edmond's honest and surprising and dreamy… Oh wait…. What this tool of characterization tells us, more than anything else, is Daisy's thoughts on each of the other characters, which (depending on how much we trust her), may or may not be the whole truth.
For example, she tells us that her evil stepmother, Davina the Diabolical, "sucked my father's soul out through his you know what" (1.4.4) and "would have liked to poison me slowly till I turned black and swelled up like a pig in agony" (1.4.5). Sure, it's possible that this is a Cinderella tale and the step-monster really is trying to poison her, but maybe we should take Daisy's claims with a grain of salt. The only thing we know for certain is that her direct characterization of others directly characterize her as readily opinionated.
Location
Are you a little tired of Daisy's comparisons of New Yorkers to English country folk? This location-based tool of characterization is used so frequently—especially early on in the novel—it's impossible not to get a feel for what the people in each location must be like. Check it:
Someone made cups of tea and they all stared at me like I was something interesting they'd ordered from a zoo and asked me lots of questions in a much more polite way than would ever happen in New York, where kids would pretty much wait for some grown-up to come in all fake-cheerful and put cookies on a plate and make you say your names. (1.3.13)
Yup, this would probably make us feel like zoo creatures, too. But more than that, it marks Daisy as decidedly different from the people she spends the book with; each time England and English ways come up, we remember that Daisy is a girl very far from home.
In addition to being polite and intrepid and competent, the Brits are also seemingly more passive than Americans. Daisy observes, "I'm not exactly in the habit of having people take over a perfectly private house to send the inhabitants off to live god knows where for The Duration, and all I could think was this would not happen in America" (1.14.3). In the Big Apple, it seems, Daisy would expect a fight. But she's not in America, so when the army comes knocking, she gets going with nary a protest.