For this project you will need:
gaffer or electrical tape
and either a disposable plastic tablecloth or crepe paper in your team colours.
Step 1: cut the plastic/crepe paper into roughly 1cm strips and lay them out on a flat surface.
Step 2: tie the strips together in the centre with string.
Step 3: push the streamers away from the ends of the string.
Step 4: wrap the string ends in gaffer or electrical tape to form a handle.
Step 6: twist each individual strand of the pom pom to separate the strands and make it 'fluff out".
I haven't made one [or two] of these since I was at school, but it was extremely quick and easy to do. You could experiment with other types of materials to use for the streamers. I chose the disposable plastic table cloth because I thought it would be more durable than crepe paper, and perhaps last more than one day. You could also use fabric, knitting yarn, or other colourful materials of your choosing.