If your four dollar cup of coffee tastes better than the stuff you brew at home, you might not be using your coffeemaker the right way. Here are the four biggest mistakes people make when they brew coffee . . .
1. Using warm or old water. Some people use warm water because they think it helps, but it makes the coffee taste stale. You should always use COLD water for a good, strong taste. And make sure you use fresh water for each brew.
2. Not using enough grounds. Don't skimp. You want two tablespoons of ground coffee for every six ounces of water.
3. Not cleaning your machine right. Most people just wipe it down and rinse the carafe. You need to clean the INSIDE too. Mineral deposits form over time and affect the taste. Fill the water reservoir with one-third vinegar to two-thirds water, and run a cycle.
4. Using old grounds. Make sure your grounds are fresh and have a strong aroma. And if you use the individual pods, keep in mind that they go stale too after a few months . . . even if they're sealed. (Yahoo)