Breaking up is hard. Whether you are the one doing the breaking up or the person on the receiving end, it is not easy. I don't believe there is a 'correct' way to break up with someone. Although you may try to avoid hurting the other party there is no pain free way to end it.
There is plenty of advice on the internet about the 'best' way to break up. I don't believe there is a one size fits all solution to the how-to-break-up dilemma. If you are initiating the break up, the way you choose will depend on the personality of you and the other party. It depends how long you have been an item, whether you are living together or not and a variety of other factors.
It seems generally people feel you should break up by arranging a face to face meeting, giving the forewarning that you need to talk. This means don't organise a date and then break up in the middle of a meal or movie. It is suggested you choose a place that isn't public. However, if this doesn't seem like a safe option then don't do it.
If you are in a long distance relationship breaking up by organising a face to face meeting probably isn't practical.
When you are living together, the situation is definitely complicated. How do you decide just when to announce your plan to break up? You can't simply say what needs to be said and leave. There is so much to sort out and each situation is different.
Sometimes we hear advice about unacceptable ways of breaking up. We hear it shouldn't be done by a text message, an email or over the phone.
It is generally considered bad form to send a break up email. However, a guy once broke up with me that way and I felt his communication served its purpose. I could tell he had spent time choosing his words carefully and I appreciated that. He expressed himself well and didn't want to hurt my feelings but felt we had no future. The email avoided awkwardness and gave me time to come up with a well thought out response.
We had only been seeing each other for six weeks so there weren't lots of things to sort out or items to return. Had we been seeing each other for longer there might have been the need for a face to face conversation to achieve 'closure'. In our situation an exchange of two emails said what needed to be said.
I don't have the answer to the question, 'What is the best way to break up?' I do feel sometimes a way which isn't generally recommended may work in a particular situation.
Whatever way you choose for breaking up, you need to get to the point quickly and be definite in what you are saying. I feel there is no way of avoiding hurting the other person to some extent. You started seeing each other with hopes of a relationship that would work. Your hopes and dreams are shattered and even if you both saw the break up coming there's going to be disappointment and pain. It's not easy for either party but life goes on.