The rule
After a meal, a weekend or a gift, thank the person in writing within two days. A handwritten note is best and a thoughtful email or message is fine. The thing that matters is that it comes promptly and it mentions something specific.
Why it matters
So few people do it that it's noticed every time. A few lines telling someone what you enjoyed turns a pleasant evening into a lasting friendship, and it costs a stamp.
How to do it well
- Keep good cards and stamps at home, so the only effort is writing.
- Mention something particular: the lamb, the story about their father, the walk on Sunday.
- Keep it short. Three warm sentences beat a page of duty.