The biggest example of this is my daily schedule these days. I sleep, eat, work, ride, read, write,chat, and watch videos. I have a pattern that requires very little thought, like being on a cruise and picking from the choices for that day that someone else has spent all the energy to organize in advance.
Some might find the regularity of a schedule (or daily outline) rather boring. I don’t. I find it wildly liberating. My mental space isn’t clogged with a bunch of unknowns that have to be worked out. But I can choose to take something that requires mental energy if I want, in a controlled way.
I remember a person in church once giving a lesson on priorities that had an object lesson involving rocks and a Mason jar and sand (or was it salt). They first put a bunch of medium and small rocks into the jar only to realize the big ones would not fit. Then they emptied the jar and put the big ones in followed by the small ones and—surprise—they all fit. It’s a pretty cliche example, but it is relevant.
Rather than stressing myself over the exact time something is going to happen during my day, I usually just have a few big rocks that I need to make sure fit into my day jar: sleep (9 hours), work (8 hours), and training (1-3 hours). These can be broken up into smaller ones but usually it makes sense to keep them together. That way I can focus 100% on that specific thing without distraction.
Work and training sometimes have specific time constraints. Training outside on a good day must happen during sunlight and when traffic is safest but Zwift training indoors can happen anytime.
Work has meetings that have to happen at certain times even though my job really has no 9-5 constraint so long as the work gets done (which is great because I can be sure I do the work when my brain is most active).
I have some medium-sized rocks in cleaning and eating.
The entertainment, reading, writing, chatting with family can fill in all the jar after the other stuff has found room.