Hey Marek, good question!
First of all, from my experience and the research I have done, most people who do certain stuff day in day out have simply built a habit of it. At one point, the behavior becomes automated, requiring a lot less willpower and motivation than it did in the beginning.
However, to get there, it can be quite a stretch. To make this period easier, I have two suggestions for you. First, procrastinate on what isn’t important, so you can focus your energy and time on what really matters (I explain why this works so well here). Second, even if your day is as packed as a Sherpa in the Himalayas, there are still tons of things you can do to destress in as little as five minutes.
Hope this helped!