Скачать или смотреть Preparatory Exercises for Vibrato by Kerstin Wartberg

Examples from the publications by Kerstin Wartberg:

STEP by STEP (Published by Alfred)
My Second Technique Book (ISTEX MUSIC PUBLICATIONS)
Enjoying Violin Technique (ISTEX MUSIC PUBLICATIONS)

Students of Charles Krigbaum from Texas demonstrate

Exercises without the instrument
Exercises with the violin or the bow
Exercises with the violin and the bow

The Finger Rolling Exercise and most of the other exercises can be performed equally well with the WRIST or with the FOREARM.

After the students have learned the basic preparatory exercises
and the finger rolling movement they will work on the three most important elements of vibrato:

1. The speed of the vibrato
2. The width of the vibrato
3. But the most important element of all is the evenness of the vibrato