Here are the DIY instructions for the pom-poms found on this nursery mobile.
Here are the things you will need:
First, start by holding the end of the yarn between your fingers.
Wrap the yarn around your fingers about 50 times.
Slip the spooled yarn off of your fingers be careful not to untangle it.
Tie the spool in the middle with a small piece of yarn.
Cut the looped yarn on either side.
Fluff the yarn to form a pom-pom cut the excess around it and you're done : )