Yesterday in the evening, it took me only one moment to decide, that I'll get up early today, although I had no lessons and not really the need to get up that early. But there were some things I had to get done though and my experience (and the statistics on Todoist) showed me, that I get a lot more done when I get up early.
So I decided and I executed. I got up early, lifted the heavy tires into the car I had to bring to the garage and did a long run, after which I took a refreshing breakfast. Running is the best morning boost ever, but I think I've said that already.
My point is, one simple decision can improve a whole day. And that decision only takes a short moment to be made. You just have to say that you will do it and then you do it. There's no magic, just a simple thought and the willingness to make it a reality.
If I hadn't made that decision, I would have reached less today. Instead of 15 tasks done, it would be only 5, I would feel bad about it.