For all of our teas except Green, use your favorite teapot and bring your water to just the boiling point, or about 210 degrees. For Green tea, boiling water is much too hot. Choose water that just starts to steam instead, about 170 degrees or so. The amount of tea needed will depend upon your taste and the type of tea that you choose. Usually about 1.5 to 2 grams will make a good standard, or about a teaspoon of black tea per cup.
Oolong is extremely coarse and requires slightly more to produce the same strength.
If you prefer stronger tea, add more. You will quickly get a feel for the perfect amount after a few cups. Green should steep only about 2 minutes, Darjeeling and Assam about 3 to 4, Ceylon and Oolong about 7, and all others taste great at about 3 minutes or so. Remember, that tea becomes bitter if steeped too long.