How to actually start and stick to no contact after breakup?

I’m really struggling with going no contact after my breakup. I’ve done it before, but every time I manage 2–3 days, I end up messaging them again. 😩

This time I really want to stop that cycle and finally let go....but I don’t know where to start or how to stay firm when that urge to reach out hits.

For those of you who successfully maintained no contact.......what worked for you? Any practical tips or mental shifts that helped you stop checking their socials, stop overthinking, or stop giving in to that “just one message won’t hurt” thought....or the "maybe one last try to get them back" thought?

Would love to hear your experiences or advice. 🙏🏻🙏🏻🙏🏻