There are some basic steps that you can take when you're looking into how to get partner back, you simply have to make sure that you get the details of these steps correct and that you spend a sufficient amount of time going through each step. How much time, varies from situation to situation and the real truth is that only you can judge the time that you think you might need.
If the relationship was a tumultuous up and down messy emotional one, then it is going to need a longer time to get over the initial mess of the break up. Longer than if your relationship was stable and less exacting. So be honest with yourself and be clear about what kind of relationship you had with your ex, because the truth right here will go a long way to helping you figure out how to get partner back.
A clue is that most people need at least a month on their own without contact with their ex to start the healing process. Don't try and bypass this alone time because without it most attempts fail.
You are going to spend your alone time looking at the mistakes that you might have made and you are going to forgive yourself for those mistakes. If you try and get back with your ex and you have not forgive yourself, then how is it possible for your ex to fully forgive you. So be kind to yourself, accept your fallibility and forgive yourself.
That doesn't mean that you just draw a line under any mistakes that you may have made and forget about them. It means that you should then go on to figuring out how you can avoid such mistakes in the future, if the same or similar situations arise. Because you really do not want to get into a cycle of the same old things that keep on happening.
Once you're confident that you have the emotions and the reasons behind your mistakes sorted out, you are then ready to go ahead and actually make contact with your ex and ask to talk to them.