Explain how to create a hook in the introduction of an essay (specifically, in an essay about "And of Clay Are We Created").

A hook must serve two purposes: it must interest your reader and it must begin to introduce your topic. There are many types of hooks that are acceptable. Three common hook types are quotes, interesting statements, and questions.
You can start with a quote from the story, but do not pick a random quote; it should tie in well to your thesis statement. For instance, you might be writing on the theme of "buried pasts." If your thesis statement addresses this theme, then this might be a good quote to open with:

There, beside that hellhole of mud, it was impossible for Rolf to flee from himself any longer, and the visceral terror he had lived as a boy suddenly invaded him.

This quote is interesting because it depicts an emotionally charged moment and contains some mystery. Readers will wonder what pushed Rolf to such a moment. Whatever quote you choose, it should not immediately be followed by your thesis statement. You would want to take a sentence or two to tie it to your main idea. To do this, explain the context of the quote. At what point does it appear in the story? What is happening when this quote appears? How does it represent the theme you are addressing?
You could also start with an interesting statement related to the story. Additionally, this statement should also set up your thesis statement. If writing about the same theme (buried pasts), you might say something like this:

Some people say to leave the past in the past, but to some people, burying the past before confronting it is like burying a piece of themselves alive.

Again, you would want to take a sentence or two to explain this concept, and how it leads into your analysis of your chosen theme.
You could also start with a question that gets your reader thinking about the topic. For instance, you could ask:

How important is it to face our pasts, especially if they are a mud pit of disaster?

Whatever question you choose, answering your question should lead into your thesis statement. For instance, this question might be followed with a comment about how "And of Clay We Are Created" would say it is very important; to not face our pasts is to remain stuck or immobile. Until the past is processed, the present cannot be fully experienced.
It is important to consider your main idea and to choose a hook that best suits it while also making sure that you maintain your own authentic voice in your writing. For example, if you are writing about character or setting, rather than theme, choose hooks that represent the character or the setting (or whatever your focus is) instead of a hook leading into a discussion of a theme. For a character analysis, it could be dialogue; for setting analysis, it could be a description.
Make sure you know what you want to say and then consider one of these hook strategies: a quote from the story, an interesting statement, or a question.