During the Holidays, everyone enjoys WOWing their guests with delicious dinners, desserts AND COFFEE!
To be a coffee-brewing-genius, you should learn a little bit about the "science" involved. In the end, knowing will help you make a really nice brew without much difficulty.
Start at 1oz Coffee PER 16oz Water. If you're brewing on an automatic brewer at home, the lower temperature (anything under 200F) isn't going to extract as easily, so add about 10% more Coffee. If you're using a French Press and can control the temperature, feel free to lessen your coffee measure by 10% or so, due to the full immersion of the coffee grounds.
Darker coffee looses some of its density during roast (along with caffeine, sugars, etc...). Because of the lost density, you should expose less of the bean's surface area to the water: ie, use a coarser grind and a little more coffee.
If you prefer a lighter roast, the coffee you're drinking is still more dense, and so exposing more surface area will allow more flavor to come out: ie, use a finer grind and a little less coffee.
Fresh grinding is SUPER important; but so is proper grinding. If at all possible, grind within minutes of brewing. As soon as the coffee is ground, you're letting aromas into the air, with means those flavors won't be in your cup. However, it is VERY important to use a good BURR Grinder (see here for a great low-cost option). BLADE Grinders chop beans in a very inconsistent way, which means the water will over-extract some of the grounds and under-extract others.
Cool, clean water makes all the difference. It makes up 98% of the final brew, so use GREAT water!
If you're using an automatic brewer at home, the coffee should be finished within 4:30 minutes. Otherwise the coffee and water have been in contact for too long, and you will end up with sour flavors on the back of your tongue- that's over-extracted coffee!
A French Press should steep for about 4 minutes. An 8 oz Manual Pour should finish dripping by about 3 minutes. An espresso should extract in about 25 seconds. If you're brewing too fast, use a finer grind and a little less coffee. Too slow, use a coarser grind and a bit more coffee.
Note: if you are using an automatic brewer, a slow brew cycle could be due to mineral build-up in the machine. If you can clean the brewer it will help, but you might need a new machine!