Print out the following PDF to get started.
Color the treasure box and graphics at the bottom.
Cut each peice out on the bottom and place them into a pile. Cut out the rectangle surrounding the treasure box.
Fold along the edge of the bottom of the treasure box as depicted.
Cut along the vertical lines, stopping at the lid.
Unfold.
Fold along the highlighted lines to help it stand up. Glue on your graphics into the inside of the treasure box.
Ta-Da!