Make your work ethic difficult for your excuses to survive around.

Excuses need a hospitable climate. They thrive where the standard is vague, where the start time is negotiable, and where nobody notices whether the work happened. When your effort becomes steady and specific, the reasons for not doing it have nowhere to settle. They do not get argued away so much as starved out by a pattern that keeps running without their permission.

Look at the one excuse you use most often and ask what condition keeps it alive. Usually it is a decision you have left open. Close it this week by fixing a time, a place, and a smallest version of the task that happens regardless of mood.