A well-expressed thank-you is an art form one can cultivate. Start with the proper stationery, keep your favorite pen and some stamps in a handy place and you're all set.
A Thank You Note Is Timely. The socially astute always give thanks promptly. Your host should receive a phone call the next morning or a note or gift within 48 hours. A thank you is like applause... it should be immediate and spontaneous.
A Thank-You Note Is Meaningful. Find a unique detail or high point to describe the evening or gift and express it in your own words. Be natural. Was the centerpiece fabulous? The food the best you've had in ages? Did your birthday gift reflect your interest in golf? Show that you paid attention and mention it.
A Thank-You Note Is Personal. There are no circumstances that excuse you from writing thanks for presents. YOU must write the note... not your secretary and, if you are old enough to write, not your mother.