One sheet of paper, one cut, and you're holding an eight-page book. Here's how the fold actually works and why people still bother making their own.
A pocket notebook, in the sense people mean when they talk about "folding your own," is a small book made from a single sheet of paper: no stapler, no glue, no binding. Fold it the right way, make one straight cut, and it opens up into eight small pages you can write, draw, or print on.
It's not a product category so much as a format. Anyone with a printer, scissors, and a sheet of paper can make one in under a minute, which is most of the point.
Fold a sheet in half, then in half again, then in half a third time, and you've divided it into eight panels. Unfold it back flat and make a single cut along the center crease, stopping short of the edges. Refold along the remaining creases and that cut opens into a spine, turning eight flat panels into eight pages you can flip through like a tiny book.
No stitching, no stapler that jams, no binding glue drying wrong. The structure comes entirely from where you fold and where you cut, which is why the format has survived as a teach-it-in-thirty-seconds trick for decades.
You can, and plenty of people do. But a bound notebook is a fixed decision: the same 80 blank pages whether you fill three or three hundred. A folded one-sheet notebook is disposable in the good sense: you build exactly the pages you need, print them from a PDF if you want specific content on them, and throw the whole thing away without guilt when it's full.
That's the gap PagePacker fills: it does the page-arranging math for you, so you can drop in the pages you actually want instead of measuring margins by hand every time.