My favorite quote by the late Maya Angelou isn't from one of her poems, and in fact there's not even a trace of it (that I can find) online.
It came from an answer to a college student's question about changing the world. She told the student that if you want to change the world, start by making your bed every day.
Because if you haven't got sufficient will and dedication to do that one simple thing, you might want to reconsider whether you have what it takes to reach your more ambitious goals.
You don't have to agree with her about this. But I do. And it's one of the only pieces of Advice from a Sage Thinker that has made any damn difference in what I do with my day.