"An IOU is a letter of recognition — a “thank you.”

Give credit to someone who sets an example that inspires you. Have the note be an “IOU” to let them know they’ve helped you in some way, whether directly or indirectly. Say thank you for what they do that inspires you to be a better version of yourself.

Borrow that inspiration to improve yourself through an Inward, Onward, Upward process.

Encourage them to reach out to you if they ever need anything in the future.