I'm often asked for best practices regarding brewing coffee. Before giving tips it's important to understand the brew process. Whatever brew method you use, heated water is acting as a solvent. Hot water is actually taking the soluble components of the ground beans away, and into the brewed liquid. Depending on what brewing method you use you may have insolubles left behind in a filter or you may allow some to pass through to the brew. For instance a paper filter will leave behind the insolubles in the filter. However, a French Press will allow some insolubles to pass into the brewed coffee. There is a good thing or a bad thing depending on your preference. A French Press that allows insolubles to pass through will add body to a cup but may also add bitterness.
The top 5 brew factors that will affect your coffee are coffee to water ratio, size of grinds, water contact time, water temperature, and agitation. Of course water quality, and coffee quality are the most important.
Water to coffee ratio is the most common question coffee lovers have. Everyone finds their personal preference but always wants to know what is the proper amount. The official answer if you were to ask the SCAA (Specialty Coffee Association of America) is 10 grams per cup of water ( a cup being six ounces).
Size of grinds is also important and varies depending on your brew method. A fine grind gives more surface area of your beans exposure to water. A drip brew will benefit from the fine grind settings on your grinder. However, a French Press will require a more coarse grind due to the longer contact and infusion.
Water contact time also will impact your brew. A drip brew should have exposure to the coffee for about 2 and a half minutes. While a French Press should be double that or more. An ideal range would fall between 4 to 6 minutes.
Water temperature for all brew methods should fall between 195 and 205 degrees. Water will act as a better solvent when near boiling.
Agitation is very important if you are using an infusion method. Stirring the brew when infusing will increase the rate of extraction.
These are just tips. Make your brew the way you enjoy it without over thinking it. With that said the basics are grind your beans just before brewing, use the correct grind, and drink just after brewing.