You should charge an appreciable percentage of the fee when booking the wedding to hold the date. You should specify in the contract signed at that time that the balance for your base fee is due prior to the wedding. Any variable charges beyond that will be based on prints, books, etc. ordered in addition to your base package and should be paid in full at the time they are ordered following the wedding.
If you are considering a wedding photography business you should consider shooting second for an experienced wedding photographer for a season to learn the ins and outs of the business.
No amount of reading in discussion forums or even textbook length tomes can prepare you properly. Just from a gear and technical expertise standpoint going in as a lead photographer with zero experience shooting weddings is a recipe for disaster. The link is to a blog written in 2010 by the head of the largest lens rental house in the U.S. regarding the mistakes people make selecting gear to rent for shooting weddings.
Gear and technical expertise are some of the least of your worries. It takes the right kind of businessperson and the right personality type to be a successful wedding photographer. Unless you are willing to be sued for far more than your original charges because you botched wedding photographs, because the lawyer you're shooting the wedding for knows how to take you for a very expensive ride and you didn't have a contract that protected you from such, or even botched the wedding itself through your incompetence, think twice about entering the wedding photography business without getting some good exposure to all that it entails by shooting a number of weddings as a second shooter to an experienced wedding pro.