Choose your setting. Many fantasy novels take place on mythical planets that are often Earth-like. Your setting will have to obey the supernatural laws that can’t be explained by science.
Develop your characters. Even though you’re writing a fantasy, your characters must base their decisions on emotions and logical processes that make sense to the reader.
Start writing your fantasy book by introducing your character in the setting you’ve selected and presenting your character with successive challenges.
Develop your storyline by having your main character interact with others. Your main character’s foe should present the biggest obstacle to your character’s goal. As your character pursues the goal, divide the storyline into logical chapter breaks.
Introduce elements of wonder into your book. These elements should be fantastic in nature, that induce awe in the reader and appeals to their imaginations.
Expand the world your character lives in as you continue writing the storyline. Go into the details of the settings. Fantasy books are generally large in scope, and you want the reader to remember the entire breadth of the world you are creating.
Write a conclusion to your fantasy book by having your main character use an element of the fantastic that has already been introduced. It’s not fair to the reader to have a new element introduced at the end of a book.