Measure the length and width of the storage box.
Cut strips of cardboard with a width equal to the diameter of the Christmas ornament plus 1/2 inch. Make the length of the strips equal to the length of the box. Divide the width of the box by the ornament's diameter and round the resulting number down to the nearest whole number to determine the number of strips to cut.
Cut strips of cardboard with a width equal to the diameter of the Christmas ornament plus 1/2 inch. Make the length of the strips equal to the width of the box. Divide the length of the box by the ornament's diameter and round the resulting number down to the nearest whole number to determine the number of strips to cut.
Make cuts in each cardboard strip perpendicular to one of the long edges that extend halfway across their width. Make the distance between the cuts equal to the ornament's diameter plus 1/4 inch.
Fit the strips together to form a grid by lining up the snips in the strips with a length equal to the box's length with the snips in the strips with a length equal to the box's width. The snips allow the strips to fit together.
Put the cardboard grid down in the box and place an ornament in each hole of the grid.