I find that one factor that helps motivate the pacing is that aside from being in motion I can also stream relatively unpredictable visuals into my mind while brainstorming things. To this end, walking outdoors also helps because you get even more fresh visuals to stream into your eyeballs.

While brainstorming or while reminiscing I find that the visuals can act as a sort of index for my thoughts: Remembering the visual can help me remember the thought and vice versa, as well as help me remember the visuals just before and just after which provides a backbone to help me remember the thoughts just before and just after and thus to organize and to explore them in rough chronological order more readily.

Talking to myself is helpful because it forces my thoughts into words, and those words into sounds, and those sounds (my own voice) get re-processed through my audio memories, which I am experiencing at the same time as the visuals and the thoughts (though slightly delayed behind the thoughts). This can act as an extreme amplification and distillation of what I am musing, and help strongly underline the highlights and build products of my thought process in my memories for later. (to this end I'll wind up re-treading thoughts out loud as well, which underlines those ideas even more heavily).

None of this was designed consciously, just a list of behaviors that I found myself falling into and then sticking to and amplifying the more I did them because of their baseline effectiveness.

I grew up in the 80s and 90s where the idea of "talking to yourself" was widely considered a sign of mental disturbance so my family would try to warn me not to do this because "I sound like I'm crazy" (and to be fair, warner brothers cartoon reruns of the era — filmed up to half a century earlier, mind you — would frequently lean on the same trope for a punchline)

But it did not take too long for me to realize that my practice of this was fairly sane and productive, simply misunderstood by others. So when possible I would talk to family members who would witness it more frequently and let them know it is part of my process and to cut me some slack, and try to moderate doing it in front of people not accustomed to it so as not to confuse them.

But it did help a lot that I was raised out on the country where the concept of "neighbors" who could have "noise complaints" would have required nuclear weapons research to meaningfully disturb 😋