Summarize:

Bring at least 1 cup (250 ml) of purified water to a steady boil using a tea kettle or small saucepan. Measure out 2 tsp (10 ml) of parsley seeds into the bottom of a teacup. Pour the boiling water over the seeds, then allow the tea to steep for about 5 minutes. Parsley seeds can be slightly more bitter than parsley leaves, so the steep time is usually restricted to 5 minutes. You can increase this time if you prefer very strong tea, however. Pass the concoction through a fine mesh tea strainer, collecting the seeds in the strainer as you do. Allow the liquid tea to drip into a second teacup placed beneath the strainer. To enjoy the best flavor, drink the parsley seed tea while it's fresh and hot. You can sweeten it or leave it unsweetened. While you can use any standard sweetener, using raw sugar or local honey may offer more health benefits than many other sweeteners can.
Boil the water. Steep the parsley seeds for 5 minutes. Strain the seeds. Enjoy.