An alternative to cutouts (usually called `thumb indexes`) is to have outside margins printed with your desired navigational aids. Consider the following two images, taken from subsequent chapters in a book:

![enter image description here][1]
![enter image description here][2]


## Update ##

In reference to another answer posted to this question, if a multi-level solution is required, something like this should suffice:

![enter image description here][3]

`A` and its sub-indexes would start at the top of the page, `B` and its sub-indexes would start in the middle, and `C` and its sub-indexes could occupy the bottom third; `D` would start at the top, and the cycle would continue. When the book's pages are somewhat "fanned", you can easily see where to jump to.

  [1]: https://i.sstatic.net/KNO1H.png
  [2]: https://i.sstatic.net/IvujQ.png
  [3]: https://i.sstatic.net/pqyQ5.jpg