Just place the two streamers on top of each other lower your presser foot on the sewing machine and bunch the streamers with your fingers and sew. That is it :)
I ran a dowel in the middle of the streamers and placed it in a basket i had. But this step is optional i just felt it kept the streamers from tangling and off of the floor.
I LOVE they way they came out plus doubling the streamers makes them durable and cute. Plus i am going to roll mine up after the party and use them again! Which with regular streamer isn't really an option.