The small square is the base of the box, the wide shallow pieces are the sides to be attached to the base and the remaining triangles are the top sides which fold down when opening the box.
Cut thin card and fabric a little smaller for the linings and make up the same as for the outer sides. If attaching ribbons to tie at the top of the triangular piece, stitch or glue them between lining and outside card now. Glue the lining inside pieces to the outer pieces including the base.
Put aside to dry.
Now attach each wider section to the base matching the shorter edge to each of the four sides of the base. Join these together at the angled sides. Now attach the wider edge of the top pieces to the top of the resulting square. Important Do not stitch the angled edges of the triangular pieces to anything else as these fold down when opening your box.
There are several ways of finishing the top point of the box. One is tied ribbons as mentioned above.
Another way is to make a triangular “cap” using the tip of the triangle as a template. This however needs to be anchored in some way as it does tend to “pop off “ all too easily. One student used a small magnet under the tip.
Another idea is to place a button or bead at the top of each triangle and tie the ribbon around this.
Yet another is to stitch a vertical loop at the head of each triangle and thread the ribbon or cord through this.