Heating the milk to 140-160 degrees Fahrenheit and then letting it cool for 10 seconds is the best way to froth milk for espresso. You can use either a manual or automatic model. Then, you'll want about five ounces of room-temperature milk and aim the nozzle just outside of the cup's rim so that it splashes and creates a thick layer. Once this layer is created, you'll want to rotate the cup in one full circle and then put it straight down on its saucer so that it settles. Keep experimenting with different techniques until you get the right consistency of foam.