Identify the character you will develop. Usually, you will develop the main character in your novel first, as that is the most important character. Give the character a name--a full name--and date of birth. Decide whether this character will be the hero, heroine, a villain or a supporting character.
Create a character profile sheet. Take a blank piece of paper, or create a form for this purpose, and put the character's name, date of birth and role in your novel at the top of the page. You will want to create a character profile sheet for each character for easy reference.
Summarize your character in one sentence. Use the character's name, role in the novel and other pertinent but telling details to help you write a brief, one-sentence summary of your character that will help you differentiate this character from other characters in your story. For instance, one character summary might be: Sally Sue Plymouth is a feisty, red-headed waitress looking for love in all the wrong places. Write that summary sentence on the character profile sheet.
Draw the character with words. "Paint" the reader a picture of what the character looks like. Make a list of the physical characteristics you will assign to this character on your character profile sheet. Include whether the character is male or female. Assign particular physical characteristics to your character including race, eye color, hair color (if any), hair length and style, presence or absence of facial hair and what kind, whether the character wears glasses or contacts (and if so, for what condition) and any other distinguishing physical features such as birthmarks, tattoos or piercings.
Describe the character's personality in detail. Make a list of words that describe this character's personality, whether the character is an optimist or a pessimist and any quirks or compulsions the character has. Make notes about this character's favorites, fears, dreams, ambitions, motivation, strengths and weaknesses and character flaws. Include all these notes on your character profile sheet.
Create a history for your character. This includes developing a brief outline of the character's level of education, degrees, alma maters, employment history, past and present relationships, current and previous marital status and hobbies. Decide where this character stands on religion, politics (including a political party affiliation) and moral issues. Decide whether this character is conservative, liberal or somewhere in between. Select a couple of key issues this character feels strongly about. Add all of this to your written character profile sheet.
Think of your character as a living, breathing being. As you write your novel, ask yourself questions. Let your character develop more completely within your novel. Pay attention to whether you have your character do or say things that are consistent with or in contradiction to her character. When your character faces a dilemma, talks with another character or does anything in your story, examine what you know about your character based on the character profile sheet to help write realistic scenes, dialogue, conflict and resolution.