This is what you need:
Garbage bags or streamers
*you can make pom-poms with garbage bags or with streamers.
- Cut the streamers into pieces about 20cm long OR cut the garbage bag into strips
- Group a bunch of strips together and secure them with an elastic band
- Glue the bunch to the top of the toilet roll, which is your handle
- Keep making bunches and gluing them to the toilet roll, until there's no more space and your pom-pom is ready.