The reader must believe the character is real. Since I write non-fiction, my characters actually lived, which makes them, by definition, real. The writer's responsibility is to make even a character that had lived or is alive seem like one about which compels the reader to want to know more.
I try to base my characters on my own life and experiences. There is a lot of me in most of them but I believe that an author needs to do one of two things to be successful. He has to either write about what he knows absolutely or write about something that nobody else can dispute, like life-after-death or Klingon Psychology.
Complexity. A character must be flawed to appear authentic.
What do they contribute in the story? Do they help or hinder the main character?
In the book, "The Muslim empire and the land of gold", the man who found the gold fields, Ophir, is known by name only in the Bible so I needed to show his background story and how he discovered these vast fields.
Dialogue is key!!! You have to actually read what you have written OUT LOUD to see how dialogue sounds. Sometimes things that look just fine on screen or in print sound ridiculous out loud, which is something you should know in case your novel gets optioned for film (haha). The biggest ‘mistakes’ I see writers of all levels making are over-writing (for instance, saying “my egregious error” instead of “my stupid mistake”), and trying to be utterly, painfully ‘correct’ at every grammatical turn. Yes, we all know that you aren’t supposed to end a sentence with a preposition—but that’s how we talk. Nobody says, “About what is that book you’re reading?” It’s, “What’s that book about?”
I don't create my characters, they're real people involed in my stories and all I have to do is put them in the right framing as the story continues and by doing so, they become believable to the reader even more so. Just as I did in my autobiography that I named "MY FATHER MY DON" a best seller on Amazon.com
You have to ask yourself, who is this person?, What makes them unique. What seperats them from the masses? Do they have a high set of morals or are the ruthless in their pursuits? What in there background influences how they see the things and how they react to the world around them? It's important to keep these things in mind so the character stays true to themselves.
Someone who has strengths, flaws and emotions. A person you'd like to meet. I create characters with snippets of people I know and a whole lot of what just become them.
Making a character believable can be challenging. Firstly, you must make sure that your character has feelings and emotions, not unlike your own. It does not matter if the character is good or bad intentioned, they still have emotions, even the most sadistic.
Creating my characters are usually quite easy. If I am creating an evil or bad character, I think of somebody I know, either historically or personally who is that way inclined. I try to put their image into my character's.
For a character to be believable I have to live the character and visualise myself as the character while I am writing. It requires moving from one character to another throughout the writing process but is not difficult. I don't actually think too much about my characters except for the basics such as deciding the sex, appearance etcetera. The rest of the character's image graduates as I continue to write. I then note down who he/she is and what his/her personality is like. It's a strange process really.
When you write biographies, you don't have that problem. Otherwise, a character must possess certain human traits, or even faults. I don't think a reader can identify with a character that doesn't reflect some kind of humanity - good or evil. It's interesting to me that animators can bring an animal or alien character to life simply by endowing it with human qualities.
I think emotional realism can make almost any character believable. We all feel joy, sadness, jealousy, empathy, etc, so by feeling out your character's emotions, you turn them into a real person on the page.
I try to create well-rounded characters, not all good or wholly bad, who the reader can identify with even if they might not know the character's hair and eye colour etc. To make my characters believable, I need to know them really well: some spring ready-made into my mind; some I have to fossick for, like digging for diamonds, finding out about their lives, their loves, their fears, their hates, their family and friends, and so on, gradually building up a composite picture and getting to know them. This usually happens during the writing of the story as I watch them in action and hear what they have to say for themselves.
Believable personality with human traits...good and bad, strong and weak. I do not create larger than life characters. I expect my characters to be down-to-earth types.
I find that everyday people under extraordinary circumstances go over well. We all like to imagine ourselves being involved in a wonderful adventure that has some special impact on the world! We may get older, but most of us still hold that magical view.