For Chinese black teas, you can go ahead and fill the gaiwan with a generous dose of tea, filling the vessel about 1/4 full. Rinse the tea and dump the water, then refill with water and steep for 1 to 2 minutes. These teas can be reinfused up to two or even more times if the tea is particularly young, with your time parameters being adjusted to taste. For the other black teas, a smaller dose and longer steeping time are generally warranted.