How do I stop Stored XSS

Hi All,
If you enter "<script>alert('xss');</script>" in to your form and save, this script get triggered on the page load. 
What is the best way to stop these Stored XSS scripts globally?
Thanks.

I'm looking for a global option where I don't have to worry about printing any stored data.

You can you entity to cast the data from the database.

Use html purifier.

What did you Try? What did you Get? What did you Expect?

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