Blueprint of storage box

Here's the blueprint of my storage box, although it's just a rough draft.


There's a board with five spikes on each side. I've decided to use it for supporting the entire box when it is in a square shape. I'm still thinking about what kind of material I should use. My candidate for board is plywood and cardboard. However, for connections of each board, it is hard to think of something that can be bent and separate. I am thinking about using rubber or ropes for these connections.