In this video I walk you through 6 quick, at-home ways to bend corrugated cardboard so your curves look clean and your builds stay strong. I start with the super simple “use a pen” trick—basically ripping between the corrugations—then move into cleaner, more controlled methods like separating the fluting with your knife (cutting straight through the valleys, not the mountains). I also show what happens when you peel off an entire face: you get a really flexible piece that can hit small radii, but it’s more fragile and the inside can look a little weird depending on which side you put the corrugation. Then I get into bending when you’re not going with the grain (when cardboard really wants to fight you). I demonstrate crushing one face with my thumbs for a fast bend that keeps both sides, even though it ends up wrinkly. Finally, I show my cut-and-split approach—cut through the top layer and the corrugation, keep your spacing consistent (my rule of thumb is about the same spacing as the corrugation), and don’t cut all the way through. The big takeaway: pick the method based on whether you need both sides to look good, how tight your radius is, and which direction the grain is running.