1. Use loose tea of good quality.
We've tried many types and continue to experiment. For our morning tea we use Murchies number 10, a blend of black teas. For evenings we try all kinds including flavoured green teas and roibus.
2. Use the right equipment.
For loose tea we use a stainless steel wire basket that fits right into the teapot. For a big pot we use a tablespoon of loose tea and fill the pot with boiling water. It must be truly boiling.
You can see here how the tea leaves have expanded in the wire basket. This allows them to release their full flavour.
(By the way, this stainless steel teapot came with us on our trips to Mexico. The spout actually came off last year and we took it to a little shop to have it welded back on. It's not pretty but it still works for us. )
Wait five minutes then give it a little stir and pour into your cups.