Growing up, I was often reminded of being too sensitive. "Don't take everything to heart, kid," my father would say. "Stop taking everything so personal! You're way too sensitive!"
Well, guess what? I haven't changed in more than seven decades of living. In fact, I've turned it into a strength in terms of writing. I can sense people's feelings from a distance, just from listening to them talk. I document these feelings on paper. Then I intuit an internal or secret life. What part is kept hidden that no one knows about? Grief? Shame? Guilt? Obsessions?
And voila! I have a character. I go beyond the basic physical description. There could be scars (both physical and emotional), a certain the set of the mouth, an odd way of walking, a look to the side, a way of folding hands, twirling a lock of hair, scratching the head or a pinching an ear. These details portray feelings central to the character.
No one gets through life unscathed. Start with basic feelings -- happiness, sadness and so on. Pull back and imagine what's lurking behind. Racism, growing old, poverty, evil, injustice, sin, ambition, deceit. The fiction writer wants to portray a concept, an emotion, an idea, but has to do so dramatically by showing and embodying the idea. Your mind is making associations -- telling you something is there and more can be revealed.
Take an image, let's say a wedding ring on your character. What is she doing with it? Twirling it around her left forefinger? Maybe around her right? Shining it with a tissue? Taking it off and on? The wedding ring alone shows something, but the action around it tells much more. Once you've nailed the gesture, explored it fully, you'll feel what the character feels.
Then what happens next?