The boxes are made out of 3 mm thick cardboard. The dimensions of the bottom, sides and lid are measured and then the pieces are cut with a cutting-knife. With a brush, apply wood glue to the edges of the sides and glue them to the bottom piece.
Usually I make a lid which sits on top of the box (same dimensions) by means of a hinge made of the same material as the lining. Then the box is lined with paper or other material. If a clasp is needed, it is fitted at that time. Then the inside is lined with thin card and decorative paper.