Choose the right purpose for the message
Decide whether the message is meant to inform, apologize, ask, support, or close a practical loop. For a message about how to apologize for damaging a borrowed item, use this factual base: name the exact action, the inconvenience it caused, and what you understand now.
Use detail that helps a decision
Include the smallest set of details that lets the recipient understand the impact and choose a response. Offer the smallest useful repair and give a realistic time for completing it. Make the immediate next step clear enough that the recipient can answer without reconstructing the entire history.
Know what the message cannot achieve
Do not inflate the apology, fish for reassurance, or demand immediate forgiveness. If the person has asked for no contact, repair what you can without sending another message. The message can offer clarity, but it cannot guarantee forgiveness, agreement, attention, or renewed contact.