To tie a balloon, blow up your balloon, pinch the bottom of the neck with one hand, and
use the other hand to stretch out the balloon’s neck a few times.
Then, pull the lip of the balloon toward you with your non-pinching hand.
Next, put the thumb of your pinching hand against that hand’s index finger, and loop
the stretched neck over those two fingers.
Finally, transfer the lip from your looping hand to your wrapped-up finger and thumb,
pull the lip backward through the loop you’ve created, and let the loop slide off your fingers
to create a knot