See how to do this on a punctured torus: http://upload.wikimedia.org/wikipedia/commons/b/ba/Inside-out_torus_%28animated%2C_small%29.gif http://upload.wikimedia

See how to do this on a punctured torus: http://upload.wikimedia.org/wikipedia/commons/b/ba/Inside-out_torus_%28animated%2C_small%29.gif http://upload.wikimedia.org/wikipedia/commons/b/ba/Inside-ou...