1. End previous relationships
If you moved things to another apartment, put a divorce stamp in your passport, or officially announced your separation on social networks, this does not mean that the relationship is over. They continue as you revisit the situation over and over again, revisit photos, spy on your ex on the Internet. It will not be possible to quickly forget about the past, it takes a certain period.
Before starting a new relationship after a divorce or separation, wait a little. Or a lot - it depends on how hard the breakup was for you. In my opinion, if the relationship lasted several years, then it is worth starting to build new ones no earlier than a year after the break.

2. Recover from an injury
Breaking up a relationship is a trauma for both participants in the process. It does not matter who was the initiator, why you broke up, whether there are reasons for joy and relief. It will hurt. Being brave and pretending you don't care is not the best choice. Ignoring the problem, mental wounds cannot be cured.
Don't rush to make new friends right away. First you need to feel the ground again under your feet and lick your wounds next to those with whom you can be vulnerable and from whom you can receive love and care. And only after that gradually go out into society and add new hobbies and activities.

3. Work on self-esteem
Breaking up hurts self-esteem. You may doubt your attractiveness, scold yourself for not being able to maintain a relationship, feel guilty. All this makes you vulnerable. You can jump into a new relationship to prove to yourself and your past love that you're still awesome. Or, on the contrary, be afraid that no one will love you anymore, and start dating just anyone.
Many are so unable to endure the pain of a breakup that they almost immediately decide to move into a new relationship. This story is very similar to walking on thin ice. And in fact, there is no resource in it - continuous internal tension. Starting a new relationship from a state where everything hurts and bleeds is like running with a broken leg and pretending like you're fine.

4. Don't Focus on Relationships
Do not make the search for a new love an end in itself. Even if you've done a lot of work on yourself, pursuing a relationship for the sake of a relationship is a weird thing to do.
At first, I generally recommend not to go in cycles in the search for a serious relationship. It is much more important to believe in yourself again, to feel desired, to increase self-esteem. It is important to gain new experience, to remember forgotten communication skills with the opposite sex. Learn to trust. As long as there are enough smooth, calm relationships (not necessarily love ones), thanks to which your life will become better.