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These ornamental balls are made from holiday cards from Christmases past. Cut out twenty circles: For a small ball, trace around the base of a jar that's about 1 1/4 inches in diameter; for a large one, trace around the bottom of a glass. Cut another circle the same size from cardboard; on it, draw an equilateral triangle, points touching the edge of the circle. Cut out triangle; trace it onto the inside of each of the 20 circles. Score, and fold along all the lines. Next, use clear-drying craft glue to join one flap each from two circles -- triangles should point in the same direction. Using the same technique, attach the flaps of three more circles to these two, forming what will be the top. Make the bottom in the same way. Glue remaining 10 circles together, this time with triangle points alternating up and down, forming a straight line. Glue the two end flaps to form a ring; this will be the middle section. Then glue top and bottom pieces to the flaps of the middle section. Use a needle to create a small hole, and hang from silver thread.