Ultimately, the best way to start a campaign for the new Star Wars (Saga) Edition of the Star Wars Roleplaying Game is by generating new characters. However, many players will want to transfer characters from the previous version of the rules outlined in the Star Wars Roleplaying Game: Revised Core Rulebook. These guidelines are designed to help you convert characters, equipment, and other mechanics from the previous version into the new rules.
Throughout the process, remember that conversion from one game system to another is by definition an inexact science. Though the guidelines provide a foundation for conversion, they can't be exhaustive, nor are they perfect. You'll see a lot of vague references to approximation, estimates, and “starting points.” You and your Gamemaster should work together to ensure that the spirit of your character is preserved during the process, even if the numbers don't always add up the same.