BUT, for the MOST part.... (Geez.)
You need lovable and memorable characters. It is agonizing to see "Mary" and "Sam" and "Bertha" and "Guadalupe" in one page, and being forced to flip back a few pages to see who Sam was.
Step One of the Secret
Make your characters memorable.
Step Two of the Secret
Make them lovable.
"How?" do you ask? I'll tell ya.
I know, I know. When I first read this, I was like, "Quirks, that's so amateurish. Quirks aren't natural to humans." But they are natural. My quirk is that I'm a Harry Potter fan (a crazy one).
When asked, "Who's SC?" someone will reply, "Oh, he's that freaky Harry Potter maniac who bought four wands and a set of robes," and the other guy will say, "Oh yea, yea, I know him." Quirks work in real life, but they are disguised as "reputation".
Dickens and Rowling are regarded as having the most fantastic casts of characters in all literature, and it all comes back to quirks -- quirky characters (and quirky does not mean comical. Understand that).
How else can we know Dobby, Sydney Carton, Mundungus Fletcher, Kreacher, Hedwig, Professor Sprout, Professor Flitwick, and Fenrir Greyback (sorry for all the HP characters -- I'm just diving into Dickens). We can barely remember the names of the parents in The Fault in Our Stars. (Loved that book, just making a point.) The more I think of it, the more I get amazed by Harry Potter. 200 + characters!!!
No two people are alike -- why make two characters in your book the same? It doesn't make sense (unless there is a reason for it).
Step Two (Again)
Make your characters lovable. How? Quirks! However, your characters' quirks MUST reveal their personality. Don't make a burly man wear high heels unless he's a model or something. (Actually, that might be pretty cool.) Characterization comes first, then comes the quirk. (I am LOVING Blogger's style options!)
Step Three (Yay, a New Step!)
Give your characters motivation. This is the secret to 3-dimensional characters. Slap them with a motivation and you've got it.
The Final, and (if You've Accomplished the Above) MOST Important Step
Your main character must have an epic character arc (not necessarily an epic plot). This is where your Frodo's and Harry's and Dorothy's come from. This is HUGE. Everything leads up to this. We go through all your character's pain (and pain and pain and pain) because we love him/her (quirks). Then, WE can experience the same resolution as he/she does. This will create an epic hero.
Don't go too crazy with a quirk for your main character. Your main character can have a quirk, but don't make it blatant. We 'become' your main characer as we read; when we look at ourselves in the mirror, we don't see a quirk -- we see a human. We see the quirks in others ;) Make your book realistic.
And please, don't make your characters something they aren't. That's the secret to a failed character. Be honest in your writing, and everything I mentioned above will come naturally. Everything comes second to honesty. That's a big deal in writing.
Hope I helped guys! What do you guys think? Any suggestions to characterization?