Too much water and too little coffee will result in over extraction. Your coffee will be bitter and you won't drink it, and then you will fall asleep at work. Not good.
50-70ml (1.7-2.4oz), 195-205 degrees, 9-10 atm of pump pressure.
Espresso machine, Tamp, clean towel
Wipe portafilter basket clean and dry and clean or purge grouphead with fresh water.
Grind and dose desired amount of coffee into portafilter basket.
Level and distribute grinds evenly throughout basket.
Place portafilter on the counter or other solid object and tamp coffee with even and consistent pressure. Keep your wrist straight and elbow at a 90 degree angle.
Clean excess grounds off portafilter handle, etc.
Place it in the grouphead and start the pump and your timer immediately. You should reach the desired volume between 20-30 seconds at which time stop the pump.
Combine the espresso with other ingredients or enjoy by itself!