Stories are about people. Stories tell us what they do or what happens to them, how they react, how they resolve the conflict in the end. Without people, there would be no stories.
In talking about this world we carry around in our heads, We must see our characters as real people. This is something I am passionate about in writing and I've said it before, but I believe it bears repeating. You must develop your characters. Without that breathe of life, they will lie there on the table, flat, lifeless, boring.
So, in developing your character, let's think about a couple of things. Your character has a past. You may want to call this "backstory." With that, let's talk about your backstory for a minute. You came from somewhere, right? Were your parents immigrants, bringing customs and traditions from another country? Were there language barriers to overcome? Was there suspicion and prejudice against your family because of your unfamiliar heritage? Listen, there are so many possibilities. Explore them all.
Here is an example of one dimensional characters, and realizing that all of America will stand up in protest, I still must call them out. Ward and June Cleaver, step forward, please.
Have you ever seen such a perfect couple? Here they are, perfectly manicured, well dressed, perfect mirror images of each other. They don't quarrel (not really), they have no differing opinions (about anything of substance anyway); it's Ward and June Cleaver, and they could be clones of each other. They have no hobbies. They seem to have no interests. They seem to have no conflicts, confusions, goals, hopes for the future, nothing. They dispense advice to their goober sons, and then June cooks a pot roast while Ward settles serenely into the couch and reads the paper. They smile benignly at one another as the picture fades. Tomorrow and tomorrow and tomorrow it will be the same.
I have no idea where they come from, who their people are, what life experiences led them to the point of the tv show. I read somewhere that June had a college education. If so, why is she picking out aprons to match her dress and planning menus everyday? Seriously. Well. Hate to say it folks, but Ward and June, well, they're boring. They are one dimensional characters, the type you want to avoid whenever possible, or just always.
What would happen if...What would happen if, one day, June snuck a cigarette into the house while Ward was at work, and smoked it? What if Ward is secretly harboring a real hatred for his job (whatever that was), played hookie all day long and went to the horse races and then, just forgot to come home for about five years? What if June took up guitar lessons and moved to Nashville to become a country singer? What if, one evening as Ward read the paper, June threw a china plate at his head because she was tired of him sitting on the couch, reading the paper every evening?
Well, we don't know and we'll never know because Ward and June amble on, eating pot roast on nice plates, and reading the paper on the couch forevermore in celluloid land.
I don't have anything against Ward and June. There is a certain coziness in predictability but, I believe you want to up the ante a bit.
Therefore, the preceding is just an example of what you don't want to do. What you do want to do is create characters that readers will bond with. The emotional attachment is the most powerful tool you have. If your readers can't or don't connect, chances are an editor or agent won't either. So, explore your brain. Go back in the murky darkness and pull out a jewel in the rough. Pour it all out on paper and see where your story goes.