You first have to identify what is important or special to her and find a way to reach her heart. Go out of your way to reach her emotionally whether that is flowers or her favorite song. She should know that you are going out of your way to get her back. Try to be sentimental and unique. If all else fails then the relationship may not be one that will work out but I would have to know I did everything I can first. Nothing beats honesty and a heart to heart talk. If you really want to know then ask the hard questions. Then work on the issue together.
If you do not choose the smiley face saying I did a great job I will not be compensated