After you have finished crying and letting all your emotional pains out, the next step you should try is getting a distraction.
After a break up an idle mind will always make you miss and think about your partner that left you, so in other to prevent or avoid another round of pain you can ease the first pain by avoiding things that can lead to that pain.
When I say get a distraction I mean distract your mind, a distraction can be anything like for example you can see some movies, listen to joyful music not depressing ones, or you can get a new hobby, just do something to keep your mind busy.
When you are certain you are fully distracted you can move to the next step.