A pot pourri varies depending upon what scented flowers and leaves you have available. You can dry fresh flowers and leaves - like lemon verbena, rose, scented geranium leaves and gardenia - on layers of paper towel in a barely-warm oven.
This is based on Rosemary Hemphill's original recipe from the 1960's, and is far superior to many of the pot pourri versions to be found in the 21st century.