After learning to assemble the instrument I usually take the mouthpiece only and begin teaching the “face funnel” so that a new pupil can have fun with a few squeaks and squawks. It is essential to funnel the air efficiently. I generally teach the embouchure first, almost simultaneously with breathing as the two are inextricably linked. Once the student has an understanding of the embouchure then a properly supported air column can be taught (See blowing pressurized air) and the “face funnel” will then do its job, blowing a thin, fast, constant stream of air. Before learning to blow, the pupil must learn the correct face shape. It is as important to show the incorrect as well as the correct embouchure shape, so that the pupil can recognize both. A mirror is useful to the student to keep an eye on the embouchure during practice. It should also be used to study the embouchure during tongued passages to ensure that the lower jaw and lips are not moving whilst tonguing.