Dave Jacobs explains that the glass needs to be dipped in water first, turning it twice. It also has to be rinced at least twice. "Next you should check the glass, it should be look a mirror, and you should certainly avoid any spots which may be left."
Open the tap at once as the beer should enter the glass in a vehement way. The glass should be held at an angle of 45 degrees when the tap beer is pouring into it. When the glass is almost full, it can be held upright. Remove the excess foam with love, and rince the ouside of the glass to remove any beer remains, Dave adds.
Dave met the challenge, since the foam was exactly 3 centimetres thick, as it should be.
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