To build the box, download the file, unzip and load the svg into Design Space (or whatever software you use).
You will need to attach the score lines, and set the blue lines to "draw" the seam decoration.
Copy the cap segment so you have 8 of these.
Keep the small octagon that is cut out of the larger octogon with the tab. Glue this to the hat base to help strengthen it.
Assemble the 8 pieces into a half-sphere. Attach the open octagon with the single tab to the bottom to strengthen it.
Assemble the two rectangular strips end to end and form a octagon. Glue the octogon with the small tabs inside it to form the "box"
Glue the cap top to the large octagon using the single tab.
Glue the box to the large octagon, centering it, and making sure it closes nicely.
Glue the hat top assembly to the hat base, lining up the large octagon to the octagon part of the base.
Glue on the brim.
Attach the "dot" at the top of the cap, if desired.
Add any logos either after assembly or before gluing the hat top pieces together.
I found it took about 30 minutes to assemble. If you cut two at a time, they will fit on 6 sheets of 12x12 cardstock.