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Put on the safety goggles and leather work gloves.

2 Grab one end of the barbed wire and bend it into a circle, using pliers if necessary. Use a cheap plastic ball as a guide for size and curves if you want a more uniform shape, or just wind it like a ball of twine.

3 Bend the end around the wire of the loop and crimp it with pliers to secure it.

4 Wrap the wire into a sphere, using pliers to help guide the shape. Continue doing this until the ball is the desired thickness.

5 Snip off the remaining barbed wire, using wire cutters. Bend the end around one of the loops of wire and crimp it with pliers to secure it.

6 Poke the ball with a blade -- if you used a plastic ball as a guide -- to deflate it and use tongs to pull its remains from the inside of the barbed wire ball.