1. Close the book.
2. Put it in your piano stool, or on a bookshelf.
3. Forget that it even exists.
Hanon is only effective when used in the way he asks you to use it. In all keys, with lots of variations and creativity. Otherwise, it is completely useless. I use technical exercises a lot, but for some reason, Hanon draws more ignorant students in than any other method to improve technique out there. It is also far from the best in that respect. Hanon can be useful, but to be used correctly, it requires maturity and knowledge on the part of the person using it. It also requires you to already have a solid technique, since by narrow repetition, all you are doing is "burning the mistakes in" and increasing your risk of injury.
By the time I would trust my students to use Hanon correctly, they no longer have a need for it.