Ideally you should have 2 teapots: one with strongly brewed tea and the other for boiling water. A formal tea service will usually consist of 2 spouted teapots, a spill pot for emptying leaves, bags, or cup remains, a sugar bowl, and a creamer- all on a tray. Sliced lemon can be added on a plate. When brewing tea, the key is to use boiling water over tea leaves ( 1 rounded tsp.) or 1 teabag per guest. Steep for 5-10 min. depending on desired strength. The tea can be diluted or freshened w/ boilng water. The host/ hostess should pour the tea.
In a pot with tea leaves and a tea strainer, not tea bags. The correct way to serve iit is how your guest likes it; what strength, milk 1st or after the tea is poured, lemon or black, in a cup and saucert.