Last week we looked at what areas one has to look at their characters when they're doing that important last revision. Now let's see what sort of things make the characters more than one dimensional.
Completeness - A number of things to look for such as names. I once read a published books where one character's name changed midway. Also looking at the names to make sure they really fit the character helps. Check to make sure if your character has red hair on page one that unless there's a reason for the blonde hair on page 100 that the hair and physical description remains the same.
As you're reading the dialogue listen to the characters. Read the lines aloud as if this was a play. Does Mary sound like Jane or like Paul. If a character is wordy or sparing with words mke sure they're the same the entire way through the story. If they have a particular background, does their language follow through?
Are their actions consistent throughout the story and if the way they respond to certain scenarios changes have you made the reason for the change in the action clear? Watch the character who reacts with physical actions and be sure this is consistent through the story. The same is true for the verbal reactor.
Characters' goals are important and so are character's fears. People always have something they worry that other people will discover. So should characters have a secret fear. This rounds the personality and makes the reader believe in this person you have created.
Read the confrontation scenes carefully. Is the reaction and reaction true to the character's nature. Confrontations are a good way to show the character as a round person rather than a cardboard cutout.