Related Clues:

• Memory jogger, maybe
• Margin jotting
• Promissory __
• A or E, or an IOU for that matter
• ___ to self
• One on the staff?
• A, in music
• Note hastily
• E or G, e.g
• B flat or C sharp
• There is an important one spelled out by the last characters of this puzzle's clues, starting from the top
• Quick memo
• Sticky writing?
• Do, musically
• It may be sticky