How does the author use foreshadowing in Looking for Alaska?

In Part Five, there are repeated references to Kevin`s hair and to blue dye, both of which foreshadow the playing of Chip and Alaska's next prank in the following section, and the reference to pornography objectifying women. This, in fact, is a frequently used motif (aspect/image) in Alaska's character, the idea that she feels strongly about how women are treated and is prepared to fight to change the attitudes that lead to such treatment. Presentations of this motif here and elsewhere foreshadow the final prank, played as a memorial to Alaska in the final moments of the book and The Eagle's commentary that he could clearly see her hand in that prank even as it is being played out.