If you and your ex have split up, it clearly shows that there have been causes for discord. What are the causes and are these causes serious? These are the important questions you should pose to yourself. The responses can assist you in figuring out how to get your ex girlfriend back.
If you went to your ex and simply state that you want her back, she is likely to look at you contemptuously and turn her back on you. On the other hand, if you went and listed to her what problems caused your rift and how these can be eliminated, she is sure to show more eagerness about getting back. Your effort will give her the messages that you are unhappy with the break-up and that you want to do something concrete to make the relationship survive.
When this truth strikes her, she is also likely to come up with her own analysis and together you can figure out how to level out all your differences and how to build a more secure and happier future. The one vital thing to keep in mind while doing this kind of investigation is to keep it impersonal and polite. If you embark on the blame game, the entire exercise will lose its purpose and may take a horribly acrimonious turn.