Choose your brew method, which will likely fall into one of several categories (batch, pourover, immersion, hybrid, vacuum, espresso).
Always grind just before brewing. Appropriate grind size is roughly proportionate to the extraction time (contact between water and coffee): fine for espresso, medium for drip, coarse for press pot.
Use somewhere between a 1:14 and 1:18 ratio of coffee grounds to water, or 2 tablespoons per 6-8 oz water. Although it’s possible to extract up to 35% of the coffee bean, the best flavor development happens when 18-22% of the bean’s mass is extracted into the water. If you follow the standard recipe, you have a great start on ideal extraction.
Brewed coffee is nearly 99% water. Use filtered water whenever possible for best possible taste and to protect your equipment. For optimal extraction, temperature should be 195-205 degrees Fahrenheit, or slightly off the boil.
Your approach will vary depending upon the chosen method, but above all, be engaged and pay attention. An attentive barista is a successful barista. Brewing variables can be barista-controlled or equipment-controlled depending upon your method (water contact time, temperature, turbulence). Turbulence, the mixing action that optimizes extraction, is impacted in manual brewing by agitation/stirring, brew water velocity, filter medium, and bubbling.
Depending upon method and equipment, you’ll need some kind of filter. Sometimes you have a choice (paper, gold, metal mesh, cloth); other times you don’t (French press always uses metal mesh, which results in a fuller-bodied brew). If you have a reusable filter, keep it clean and free of clogs.
Keep brewed coffee in insulated pots for a maximum of two hours, and never add fresh coffee to stale coffee in an airpot. Always rinse carafes/airpots before refilling. Coffee should never sit on a warmer/burner.