Steps/Methods Fold the long side of A4 paper in half and cut it into two halves, one half is used to fold the box body and the other half is used to fold the box cover. Point the long side of the rectangle at yourself. If there is a painted face, the painted face will face down. Fold the rectangle up and down and open it, leaving a long center line. Align the upper edge with the center line and open it, leaving a line of 1/4. Then aim the lower right corner at the top, press out the upper half of the bisector of the upper right corner and open it. ...