A simile is a figure of speech in which two unlike things are explicitly compared usually using the word "like" or "as."
Furthermore, as you start to point out, Creech has sprinkled similes throughout her book. For example, in Chapter 10:
"Being a mother is like trying to hold a wolf by the ears," Gram said.
Looking for more? Check out what the adults, especially Gramps, Gram, Dad, and Mr. Birkway, say to Sal about how to look at life.
However, in Walk Two Moons, the most important similes are the ones that readers are expected to complete on their own. For example, in Ch. 19, Sal's father says to her:
"You're trying to catch fish in the air. Your mother is not coming back" (Ch 19, p.115).
What is the other half of that simile? What is Sal's father suggesting is like trying to catch fish in the air?
The most important simile the reader has to complete on her own is the one that gives the book its title, Walk Two Moons. In Chapter 9, Creech gives the reader the first half of this simile through a proverb left by a "lunatic" on Phoebe's doorstep:
Don’t judge a man until you’ve walked two moons in his moccasins (Ch. 9, p.51).
By chapter 44, “Bybanks,” Sal has figured out the simile. So, she and Gramps take turns pretending that they are walking in someone else’s moccasins until Sal makes an unexpected discovery:
We walk in everybody’s moccasins and we have discovered some interesting things that way. One day I realized that our whole trip out to Lewiston had been a gift from Gram and Gramps to me. They were giving me a chance to walk in my mother’s moccasins—to see what she had seen and feel what she might have felt on her last trip (Ch. 44, p.276).
Can you figure out the simile based on the passage above? Walking two moons in a man's moccasins is like ... ?