The best (and funniest) example of foreshadowing is when Minny shows up at Hilly's house with a chocolate pie. Because Hilly is so pretentious—and because Minny is a strong character with a good dose of sass—the reader has a feeling that this isn't just a peace offering. Seemingly oblivious to the idea that anyone would dare challenge her, Hilly eats two slices, unaware of what the pie really contains: human excrement. This foreshadows bad things to come for Minny as the reader is certain of Hilly's racism and vindictive nature.

Sure enough, when Hilly discovers the truth, she sets out to destroy Minny in every way. But the reader becomes aware of a further truth: it would mortify Hilly if anyone ever discovered what had happened. This foreshadows another truth: Minny actually has the upper hand here and will use it to level the playing field in this secretive game. (The women include this story in their book as a means of keeping Hilly quiet and keeping themselves safe in their town full of racism and violence.)

A second piece of foreshadowing is a piece of advice Skeeter is given from Elaine Stein: "Write about what disturbs you, particularly if it bothers no one else." Skeeter really ponders this advice and begins to consider her close relationship with Constantine. This piece of advice foreshadows the book that Skeeter will eventually write about the injustices that the black maids suffered in her town.

Constantine herself provides some foreshadowing in a conversation with Skeeter, who reflects:

Even though I felt miserable, and knew that I was most likely ugly, it was the first time she had ever talked to me like I was something besides my mother's white child. All my life I'd been told what to believe about politics, coloreds, being a girl. But with Constantine's thumb pressed in my hand, I realized I actually had a choice what I could believe.

This foreshadows Skeeter's break with her community's values and even the values of her family. The reader is aware that Skeeter is going to make her own way—valuing people over prejudices.

Foreshadowing is a technique used repeatedly in this novel. At least two of the first examples take place in the opening chapter. 

The nature of Aibileen's conflict with Miss Elizabeth is foreshadowed in one of the initial details she shares regarding Elizabeth's relationship to Mae Mobley. Elizabeth refers to her baby daughter as "it" and this detail hints at the work Aibileen will later do to counteract Elizabeth's lack of care for Mae Mobley.

The use of "it" is followed by Aibileen's realization that "something is wrong with this situation." This statement foreshadows the full disclosure of Elizabeth's lack of warmth. 

Also in the first chapter, Hilly mentions her initiative to have separate restrooms put into all the houses where African American help is employed. The mention of the initiative foreshadows two things. First, this foreshadows the construction of the restroom in the Leefolt house. Secondly, this foreshadows the dynamic which will dominate the narrative where Hilly's opinions antagonize those who disagree with her. 

Later, Minny's encounter with Mister Johnny is predicted when the meter man comes to Miss Celia's house. Minny and Celia spot someone and do not immediately know who it is. Minny hides in the bathroom.

She looks into the mirror and sees herself there, “crouched like a fool on top of a white lady’s toilet,” ruing that she has been reduced to doing this to make a living.

This scene predicts Minny's eventual encounter with Johnny. 

Identify an example of foreshadowing in The Help.

I think that one of the strongest examples of foreshadowing in the novel comes from Abileen's most foundational understanding of being in the world.  She views consciousness as something that hinges on the potential for redemption and solidarity amongst human beings.  This is seen early on in the novel and helps to foreshadow the elements that will shape it:

The thing is though, if I start prayin' for Miss Skeeter, I know that conversation gone continue the next time I see her. And the next..cause that's they way prayer do. It's like electricity, it keeps things going.

This is an element of foreshadowing because it is a concept relating to the novel's theme early on in the text and continues throughout it.  Such an idea underscores Skeeter's attempts to help the African- American women as well as helps to underscore how Abileen will stand up for her own sense of rights, bringing out the element of "electricity" that exists within solidarity.