What you need to do to right the wrongs is to fix the areas of your relationship where you were culpable of the problem.
This is going to take time and it is going to require patience.
Relationship ending problems do not creep up overnight, and they will not be solved in that amount of time either.
This is the time to carefully, and as objectively as possible, look back up the relationship to look for signs of things that were going wrong.
As your ex is likely to be very angry at the moment, it is highly recommended that you employ the No Contact Rule and cease all communications with your ex for awhile - this is part and parcel to make your ex fall in love with you once again.
The No Contact Rule gives the both of you the time and space you need to move on from the negative emotions the breakup elicited, as well as to evaluate your union and where things went wrong.
Time apart also allows for the two of you to begin to genuinely miss each other, and one another's company.
This is why the No Contact Rule is so effective in one's efforts to make your ex fall in love with you again.
By its very nature, it gives you and your ex exactly what you need - time.
Though it will be, by no means, simple to work through all your problems and resist the urge to contact your ex, if you can hold strong, it will pay off in the end.
Resorting to desperate tactics to get your ex back do not generally result in a happy ending, and it is important to avoid doing anything rash and sticking steadily with the No Contact Rule.
Sooner or later, your ex will want to get in contact with you, and you can show them how much you've changed in your self-improvement efforts.
They will likely be blown away by the new and improved you and want to work to give the relationship a second chance.