The German consonant 'w' is pronounced like an English 'v' in the words 'very' and 'video'. The sound is also represented in phonetics by the phoneme 'v'. Although this may take some getting used to, the articulation of the sound itself is one with which English speakers are familiar. In both languages, the upper front teeth and the lower lip come together to form a narrowing through which the air passes with a trace of a hiss. It is called a 'fricative' consonant, which means that is articulated by forcing air through a narrow gap in the vocal tract in such a way that friction is audible.
The /v/ phoneme, the sound that is made when you say the German letter 'w', is thus formed in the same manner and the same place as the German /f/ phoneme. The difference is that you use your vocal cords to make the /v/ sound, but not when you articulate /f/. To feel the difference between the two consonants, place your hands over your ears and repeat the German words fein and Wein (which begins with the /v/ phoneme, despite its spelling). When you say fein, the only thing that should hear is the airstream passing out through your mouth. But when you say Wein, you should be able to feel your entire head vibrate.