If you intend to publish a novel, it is important to determine how much allegory you want to put into your story. Allegory is the underlying meaning in a book, usually personified by a character or story theme. Allegory is an abstract method of formulating a novel, used for making observations on political, sociological, philosophical, mythological, historical and religious ideas.http://literaryzone.com/?p=153

Allegory can be tied to metaphor, foreshadowing and point of view. Each element uses characters, themes and settings to symbolize a deeper meaning.http://literaryzone.com/?p=153 It is a good idea to keep your audience in mind when writing an allegorical novel. Some may not understand it or even see that allegory to some bigger issue was even there in the first place. 

If you intend to make your novel symbolize a deeper, conceptual idea, it is important to consciously figure out how you will implement it in your book. Creating a detailed outline can help you to organize your allegorical elements and allow you to lay them out effectively across your novel. It's important to keep allegory simple as it can quickly become complex.http://www.youtube.com/watch?v=yJCvEhL7FuA

Making a narrative story into a symbolic story is what allegory is about. Keep that in mind when infusing ideas from your outline into your novel. Don't encumber one portion of the book with a lot of allegory and leave the rest without any - unless you are approaching your novel with a stylistic structure. Otherwise, a balance should be maintained so the reader is reminded of the allegory but not suffocated by it.http://www.youtube.com/watch?v=yJCvEhL7FuA

While intending to make a symbolic story is one approach to having an allegorical novel, some authors create works of allegory without intending it. After your novel is published you may find that your book is interpreted in several different ways, many of which you did not intend. These are levels of allegory that are specific to the reader.http://www.youtube.com/watch?v=yJCvEhL7FuA