Shoot for a 1:16 grams of coffee to water. For pour over, we like 22 grams of ground coffee to 350 grams of water. If you tend toward barbarism and prefer tablespoons, aim for a heaping tablespoon of coffee for every 4 ounces of water.
Don't brew with tap water. Instead, brew with filtered or bottled varieties. Testing has led us to conclude that Arrowhead and Crystal Geyser are the best bottled varieties in the SoCal area. You can also use your home purification systems or even standard Brita filters.
If you're not grinding fresh, no amount of roasting sorcery will save you. Good coffee demands a grinder (preferably a burr grinder), and great coffee demands the proper grind size. For espresso and moka pots, your grind should look like powder. For drip and pour over, your grind should look like kosher salt. For French Press, your grind should look slightly larger than cornmeal. If your coffee turns out bitter and sludgy, grind coarser. If it turns out watery and sour, grind finer.
Coffee won't brew optimally if it's not subjected to hot enough water. That means your water should strike the grinds between 195 and 205 Fahrenheit. That does not mean, however, that you should pour water in that temperature range. As water cascades from the spout of a kettle it cools -- considerably. For that reason, we suggest you use water about thirty seconds off the boil. Our favorite pouring temperature is 207 Fahrenheit. We use it for everything from pour over to press pots.