Heat a kettle of water. Don't use water that's been sitting in your kettle, which can pick up off-flavors or become "flat" from repeated boiling. If you live in a hard water area or your tap water just tastes bad, put it through a water filter first.
If you don't have a kettle, microwave a mug of water before adding the coffee.[5] Microwaved water can "explode" if overheated. Prevent this by putting a wooden popsicle stick or teaspoon of sugar in the cup