Trace something square shaped onto your cardboard box nine times. The size of the squares is up to you. Cut them out.
Trace the same square shaped thing into the centre of nine plain pieces of paper. Draw anything you like in the squares.
Let's say that this is your piece of paper and the yellow square in the middle is the square you traced and drew on. Now cut along the dotted lines, turn the piece of paper around and put double sided sticky tape onto the remaining flaps (orange in the picture).
Put your piece of paper over the cardboard square so that the squares overlap. Glue the flaps down onto the cardboard and hang :)
You can replace white paper with several patterned pieces of paper, wrapping paper, it's up to you and your imagination!
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