I can't speak for them, but my own case was similar. For me it was a long process of making the bad habits harder and good habits easier. I deleted my League of Legends account (this improved my life by far the most of these changes) and blocked a bunch of sites on my browser. I started taking more walks, began getting up at a set time which I gradually shifted earlier and earlier, and started working more.
It sounds cliche, but it has worked exactly that way for me. A little more good habits, a little less bad habits, repeat x1000 and you're a whole new person in a whole new place.
