Material preparation: alcohol lamp, beaker, cocoon, match, warm water, stirring rod, iron shelf, asbestos net and paper tube.

1. Light the alcohol lamp with a match and put it under the hob. Add half water to the beaker and heat it on the asbestos net.

2. Put the soaked cocoon into a beaker, stir it until the water boils, and continue to heat it for 2~3 minutes.

3. Remove the alcohol lamp and put it out, and let the beaker and cocoon inside cool naturally.

4. Take out the cooled cocoon, and randomly take out a silk and wrap it around the paper tube.

5. Continue to rotate the paper tube until all the cocoon filaments are drawn out.