The same rules of attraction that allowed you in the first place to get together with your ex girlfriend shall once again come to your rescue now that you are trying to figure out how to get your ex girlfriend back. Remember how many of your friends said that you should not look like the good guy infront of her if you want her as a girlfriend? That applies really well over here too. Never let your ex think of you as a good guy because such guys are better off as friends rather than boyfriends for girls.
They want someone who is not always around, who is not their lap dog looking to please them for a treat in the bed. They want someone bold, confident, attractive and aggressive in whatever they pursue. Remind your ex about all of these characteristics in you and before you know it she will be well on the way back into your outstretched arms.