I used to just cut the top off of the box using a kitchen knife. I would start just below one of the corners, with the box on it’s side, and I sawed through it.

I got some funny looks for that one when I first did it on autopilot around other people lmao.

You know that the serrated lines on the box aren’t great when cutting the cardboard with a kitchen knife is legitimately easier. The blade wasn’t even serrated.

The post does not say that you will be able to penetrate with the index finger. It just recommends to place the finger that way.

Look at the girth of that dude’s index finger. No wonder it works for him.