Sequence index: Living Luminously
Previously in sequence: City of Lights
You can use luminosity to help you effectively change yourself into someone you'd more like to be. Accomplish this by fixing your self-tests so they get good results.
You may find your understanding of this post significantly improved if you read the seventh story from Seven Shiny Stories.
When you have coherent models of yourself, it only makes good empirical sense to put them to the test.
Thing is, when you run a test on yourself, you know what test you're running, and what data would support which hypothesis. All that and you're the subject generating the data, too. It's kind of hard to have good scientific controls around this sort of experiment.
Luckily, it turns out that for this purpose they're unnecessary! Remember, you're not just trying to determine what's going on in a static part of yourself. You're also evaluating and changing the things you repudiate when you can. You don't just have the chance to let knowledge of your self-observation nudge your behavior - you can outright rig your tests.
Suppose that your model of yourself predicts that you will do something you don't think you should do - for instance, suppose it predicts that you will yell at your cousin the next time she drops by and tracks mud on your carpet, or something, and you think you ought not to yell. Well, you can falsify that model which says you'll yell by not yelling: clearly, if you do not yell at her, then you cannot be accurately described by any model that predicts that you'll yell. By refraining from yelling you push the nearest accurate model towards something like "may yell if not careful to think before speaking" or "used to yell, but has since grown past that". And if you'd rather be accurately described by one of those models than by the "yells" model... you can not yell.
(Note, of course, that falsifying the model "yells" by silently picking up your cousin and defenestrating her is not an improvement. You want to replace the disliked model with a more likable one. If it turns out that you cannot do that - if controlling your scream means that you itch so badly to fling your cousin out a window that you're likely to actually do it - then you should postpone your model falsification until a later time.)
Now, of course figuring out how to not yell (let us not forget akrasia, after all) will be easier once you have an understanding of what would make you do it in the first place. Armed with that, you can determine how to control your circumstances to prevent yelling-triggers from manifesting themselves. Or, you can attempt the more difficult but more stable psychic surgery that interrupts the process from circumstance to behavior.
Sadly, I can't be as specific as would be ideal here because so much depends on the exact habits of your brain as opposed to any other brains, including mine. You may need to go through various strategies before you hit on one that works for you to change what you need to change. You could find that successful strategies eventually "wear off" and need replacing and their edifices rebuilding. You might find listening to what other people do helpful (post techniques below!) - or you might not.