I can't get it to work using any of the existing answers to this question. I have a box that has been subdivided.
I want to cut a square hole into it. I've tried using Knife Project and the Boolean modifier to cut the hole but I get the same kind of result. In both cases there are weird artifacts in the hole.
In the other questions about this type of problem they were saying something about how the subdivision modifier works better with quads but I'm not sure what that means. They were trying to cut circles and I'm trying to cut a square and a square has four points so I was hoping it would just magically be a quad or something.
Can you advise on how to cut this hole?