How to Play the Violin
Bow at right angles to the strings
Move the bow across the strings at right angles. The basic position is between the end of the fingerboard and the bridge.
The violin is played with the bow, not the hand
The violin is always played with a bow, not with the hands. The hand only helps the bow produce the most beautiful sound that it can. Thus, the strength used to support and move the bow should always be kept to the absolute minimum, and being able to bow smoothly and naturally with only the weight of the bow and the arm, produces a beautiful sound. However, most beginners often cannot help but grab the bow with a firm grip. When this happens, rotate your right shoulder several times to relax it. It will take a little time before you get the hang of bowing.
From Yamaha Music Media, "Beginning the violin," by Chihiro Murakawa