Things you'll need: A hand (yours) A mouth (sorry, Hello Kitty! and I was trying to be funny when I said that) Lungs (yours)
Step 2: Lip Position
Put your lips in the bottle blow position. (If you're having trouble, look at the image)
Step 3: Hand Position
Put your hand out, but bend your hand like the images and put your thumb at the side and make a gap between your index finger and thumb.
Step 4: Making the sound
Put your mouth on the gap and inhale (suck in). If done right, it should make a whistling sound. To shape the sound, you can say stuff while inhaling without using your voice. For example, tooka tooka. Experiment with your mouth and tongue and find a good balance.