Mother communicates through various idioms throughout the story. For example:
This is how to make ends meet.
This is a straightforward usage of an existing idiom. "To make ends meet" means to manage with very few resources. In other instances, Mother says things that have both literal and commonly known figurative meanings:
This is how to catch a fish; this is how to throw back a fish you don’t like, and that way something bad won’t fall on you.
Advice on fishing serves as practical advice for feeding oneself, akin to Mother’s instructions on growing okra. Because it is immediately followed by “This is how to love a man,” it also evokes idioms like "Plenty of fish in the sea"—an idiom that refers to romantic prospects as fish to be caught; Mother could also be describing how to find a man and how to discourage one.
Similarly, Mother riffs on other idioms when she says:
This is how to spit up in the air if you feel like it, and this is how to move quick so that it doesn’t fall on you.
This is a variation of the more common idiom "Don't spit in the wind" and also plays on the idea of not spitting directly up into the air. Conventionally, this expression would warn against futilely doing something that will make no difference—it's an expression akin to the idea of trying to swim upstream. Here, however, Mother subverts the idiom by teaching her daughter how to spit into the air in a manner that avoids the repercussions. She doesn't condemn the impulse or the desire to spit in the air, a presumably unladylike expression of frustration or joy. This same kind of pragmatism is reflected in her frank advice regarding abortions.