Making good coffee isnt as simple as just setting your coffee machine. Making bad coffee is much easier to make, but if you want the best cup of coffee then you need to take care of certain things before you pour the first drop.
If you want the best brew then make sure you have cold water in your machine. Dont use water that is hot or has been boiled already, if you want even superior results than use cold water that has been filtered or is bottled. If your home has old pipes and nasty tasting water than this can further affect the taste of your coffee. If your town has a lot of chlorine in the water or if it is very hard this can also affect the taste of your coffee.
The temperature of the water is key to the brewing process. 195 to 205 degrees is the best temperature to make sure that your coffee is brewed properly. If the water is too hot it can cause the coffee to be bitter, but if it is too cold then it wont absorb the flavor properly from the coffee grounds. Try Bunn Coffee Makers for a product that has great temperature levels.
If you are pressing your coffee then wait until the second after it boils to use your water. If you pre-heat your coffee pot...