My third cardboard recycling project helped me solve another ongoing problem: finding sticky note pads. I own dozens in different sizes and shapes, and yet when I need actually one I find they've all migrated elsewhere (generally with the help of whoever last used it.)
To keep the sticky note pads I use most often in one spot in the office (and to make them harder for the family to filch) I used my cardboard to create a sticky notes caddy, as follows:
First I worked out how many notes I could fit on each side of the cardboard by arranging them until everything fit the space.
I then marked the cardboard with a marker by making a line at the top of each note pad for placement and as a cutting guide.
For the note pads that had strong, bendable backings I used a box cutter to cut a slit just below the placement line for that pad. When you do this, remember to be careful with the cutter or cutting utensil you use (most of them are insanely sharp), and work on a surface like a cutting mat, a piece of scrap wood, a bundle of newspapers or whatever you have that won't be ruined by the cutting process.
For the note pads that had flimsy backings I applied some strips of double-sided tape and stuck them to the carboard.
The first time I tried this I put the note pads on both sides inside the cardboard piece to make it more like a book, but that turned out to be a bit bulky and hard to keep closed. I thought about refolding the carboard, but decided to put half the note pads on the outside and half on the inside, and that worked better for me.