How to become a writer of habit?

A lot of authors will give the advice, Write Every Day. No exceptions.

A lot of other authors will give the advice, OMG, you don’t have to write every day. I don’t. You don’t either. Don’t listen to that advice.

Neither of these are correct and neither of these are wrong.

What you must do as a writer is create a habit. A habit that will last you through shitty days. A habit that will last you through null motivation. A habit that will last you through depression ...