Step One: Fold your felt in half and draw the shape of your ears onto one side of the felt. I made mine with cat ears, but you could do anything from a mouse to a dinosaur (actually, I don’t think dinosaurs have ears).
Step Two: Cut out your ears, making sure you cut both sides of the felt. You should now have a shape that looks a bit like this:
Step Three: Sew on any other parts of the ear you want. I added little white bits to the middles like this:
Step Four: Wrap one ear around your headphone, making sure to pull it tight. Sew around the edges using a tight blanket stitch (you can find out how to do this on YouTube) or just a normal running stitch.
Step Five: Do the same with the other ear.