Grab your phone and set your timer for 1 minute.
Softly purse your lips. As you inhale through your mouth try to make a high pitched whistling sound.
As you exhale make a whistling sound for as long as you can.
Exhale, whistling as long as you can.
Close your eyes and focus your attention on the sound of the whistle without judging the quality of the sound.
When the timer goes off, if you can hear it, stop.
Notice how you feel.