Things You'll Need
Instructions
Stretch the neck of the water balloon over the end of a hose or water faucet. Pinch your index finger and thumb together around the end of the hose or faucet to prevent the balloon from popping off.
Fill the balloon 3/4 of the way from the top with water while you support it with your other hand. Move your thumb and forefinger down the neck of the balloon and pinch it tightly while still supporting the balloon with the other hand. Allow gravity to pull the stretched neck of the balloon from the faucet or hose.
Rest the balloon on a flat surface while you pull the neck of the balloon upward and wrap it all the way around your first two fingers twice.
Push the neck opening of the water balloon between your first and middle fingertip and pull it through the wrapped portion of the balloon neck on your fingers.
Allow the weight of the filled water balloon to pull the knot tight and slip the knot off your fingers. Pile your knotted water balloons in a laundry basket or bucket until you are ready to use them.