I've been spending a lot of time recently re-learning vibrato. Years of bad habits left me with a weird uncontrollable finger vibrato. As a result, I have been practicing in front of a mirror a lot lately. Why? There's no better way to learn a physical movement than to get real-time feedback on your movements. The violin is physically difficult to play. Every part of your body needs to be aligned in order to make a good sound. The ABSOLUTE best way to fix your position and improve your sound is to practice in front of a mirror.
Practicing in front of a mirror isn't very difficult, but it's extremely important and not very many people do it. So here's a brief overview of how to do it!
Find a full-length mirror. Practice long bows SLOWLY and focus on one part of your body. Then ask yourself the following questions:
- Am I relaxed?
- Is my right shoulder relaxed and down in the socket?
- Is my bow moving perpendicular to the strings? It should be.
- Is any part of my right hand straight? If so, relax it and make it bent.
- Is my left wrist collapsed? (Is it parallel to the neck?) If so, lower your wrist.
- Is my left thumb high above the fingerboard? If so, lower your thumb.
As you play, pay attention to your body and the way your fingers move. Everything should be relaxed and moving naturally. Simply observing yourself play, even if you don't know exactly how you should look, should help you correct your posture.
Beyond that, you'll begin to notice yourself correcting bad posture and habits. It's imperative that you understand what correct position looks like, however, for skills such as vibrato. If you don't know what you should look like, you won't be able to fix your mistakes.