Keep the following 12 commandments in mind. My advice would be to go through a character questionnaire and figure out how much you know about your character. These books include illustrations, in lesser measure as the word count increases, stopping around Middle Grade. Go this route if you have a lot of patience and you want the book to reach a wider audience.
Listen to conversations you hear around you; none of them will sound like the nicely flowing, full sentences you learned to write in school.
Figure out how your book is different than the published ones. It could be a mystery, it could be a person, it could be a crisis of confidence. Use this book dummy to layout your scenes and choose where in your story you want the page to turn.
Lay your subject out simply, but not simplistically.
Start your book that quickly as well. Human, animal or alien?
If you go the traditional publishing route, the publisher will copyright it for you. Also, the title is the number one marketing tool of your book. Only use rhyme if you are sure your story needs it and every word is moving the story on.