How do you make a perfect pour from a bottle, given a typical non-widget, non-bottle-conditioned beer? Is there a special technique used to make a nice foam collar (not too much, not too few)?
To pour a beer you take a clean beer glass, preferably those made by the brewery specifically for their beer. You hold the glass at 45 - 60 degree angle and gently pour the beer into the glass. You then move, after pouring half of the beer, the glass into the upright position as to make a foam colar of about 2 cm.
Depending on the beer you should or should not empty the bottle completely. Very old beers should be poured carefully as they have a lot of sediment on the bottom. Younger beers can have sediment as well, but can still be drunk. The beer will get a more bittre taste if sediment is poured a long as well.
Speed is also important, depending on the temperature of the beer, it can foam more. There are beers which have their own specifc pooring prescription. Some beers like Duvel actually need to be "dumped" into the glass with a vertical poor. Others like Guiness use a double poor.