Writing a story about a hero isn't just for fantasy or science fiction. Most stories have a hero, usually the main character, who undergoes a great trial and is rewarded at the end. Heroic stories inspire an audience and remind us of our own capacity for greatness. Joseph Campbell is famous for his study on the "hero's journey," a narrative pattern where the hero follows classic motifs.
Know what is heroic. Merriam-Webster's dictionary defines a hero as "one who shows great courage" or "one admired for his achievements and noble qualities." Books and films are replete with heroic figures. A couple of examples include Luke Skywalker from "Star Wars" or Harry Potter. While some heroes may start out as cowards, they do not remain that way.
Begin humbly. Heroes usually start from nothing and have only humble desires until circumstance forces them to act. For example, the character of William Wallace from "Braveheart" doesn't want war; he just wants to live a normal life. But he is propelled into action when an evil lord kidnaps his wife-to-be. Luke Skywalker lives on a barren planet far from the action of the galaxy. It is only when Luke sees the video from R2-D2 showing Princess Leia's plea for help that Luke begins his journey.
Create great obstacles. Make sure your hero is facing obstacles worthy of your hero. If your hero can easily finish his mission -- if he can easily rescue the girl, for example -- then how heroic is he? He needs to face a task that most men find daunting. When we think of heroes in our everyday lives, they are usually people we look up to for their courage, fortitude and daring.
Create a compelling villain. Your hero is only as strong and courageous as the villain he must confront. The more interesting and powerful your villain, the harder it is for your hero to succeed. Your villain must be proactive as well; a villain without a plan for destruction is passive and, therefore, not a threat. Your villain must set forth on a path that directly intersects with your hero's journey. Note that not every villain is a person; sometimes the villain is the environment. If your hero is lost in the Arctic Circle, then the elements of frost, cold, wind and lack of food become the villain.
Create worthy goals. Heroes represent the best of us. Make sure that the goal of your hero is worthy. If your hero is stealing money from the rich, that's not a hero; that's a thief. But if your hero is stealing from the rich to save the poor, then you've got yourself Robin Hood, a hero by anyone's definition. The firefighters who ran up The Twin Towers were heroes because they put their lives in danger for a good cause greater than themselves. Make sure your hero does the same.
Populate your story with friends and guides. Heroes need help, even if they are heroes. Who would Luke Skywalker be without the help of Han Solo or Princess Leia? What about Frodo without Sam from "Lord of the Rings"? Or Harry Potter without Ron and Hermione? Give your heroes characters to guide them along their journeys.
Give your hero a flaw. What makes your hero a hero is not that he is all-powerful. He is an ordinary person moving in the face of extraordinary circumstances. That's what makes him so special when he achieves nearly unobtainable goals. If your hero is infallible, then he becomes boring and one dimensional. Give your character a flaw so that your audience can relate and sympathize with him.
Create an "all is lost" moment. Every great hero story has a moment near the end where it seems as if all is lost. The mission looks to be a failure and your hero is at the lowest point of his journey. For the moment, he loses faith. The "all is lost" moment forces your hero to make the ultimate heroic choice: to quit or continue. She ultimately chooses to continue, even in the face of terrible odds. This is what defines your character as a hero.
Build toward a climax. At the end, your hero must confront the villain by himself. For example, if the villain is a dragon, then the hero will enter the cave alone. Most importantly, the hero must vanquish the villain. Heroes can die in the confrontation, but they must ultimately defeat the villain first.