Be a secret drinker. Teapot cocktails are a sneaky way of adding more alcohol to your event and always a great way to kick things off Innocent bystanders will just think you are drinking plenty of tea.
My suggestion is to pour these cocktails into clean teapots and top them up as and when. While my largest teapot contains 800ml and my smallest 150ml, the average teapot contains 500ml. The average teacup contains 150ml, so I will suggest servings in terms of cups and you can adjust this to the size of your teapot.