You have to decide what your highest priorities are and have the courage—pleasantly, smilingly, nonapologetically, to say “no” to other things. And the way you do that is by having a bigger “yes” burning inside.
-Stephen R Covey
What's "the rest"? The rest of my interests, as a person. And also rest, as in recovery.
I'm naturally curious about many things, and I read and talk with experts in other domains. Formally, this is called a "barbell" strategy: I invest in learning about my area, but also keep some time to study ideas in other fields (Machine Learning, Quantum Computing, Computational Biology). This is both a privilege as an academic, and a duty: it's how I invest in having new ideas tomorrow.
I also find that "...the tired parts of the mind can be rested and strengthened, not merely by rest, but by using other parts."
My values inform how I balance multiple needs – between research and teaching, or between work and life responsibilities. In this regard, I believe in being explicit and planning ahead, so no one gets sudden surprises. It's important to me to be trustworthy, so I set clear boundaries regarding how much I can and cannot do. The same applies to how I mentor students or lead a group.
I believe in old-school grit and patience. It's important to pay one's dues, and learn. "And it's that process that is the magic."