A proper playing position means a lot for any string instrument players. Considering how long you would play on the stage and also the genre of your music, you need to make sure that you are comfortable throughout the show.
For a viola player, proper posture is the key to a pain-free set-up that would allow you to finish every piece gracefully. Your body and your instrument will become one, ergonomically speaking, while performing so you have to consider the following tips:
Hold your viola horizontally sloping in the middle, so the bow is parallel to the floor, with your left hand touching lightly the neck part of the instrument. Get in position and try lightly gripping the fingerboard a few times to know if you’ve placed the viola right without tension.
Lean the body of the viola on your collar bone and place your left jaw on the chin rest. You can also use a shoulder rest to help you hold up the viola and make it more secure. Take note that a shoulder rest should not be squishy.
Your head should be balanced and free from moving. If your head is stiff, you’re not holding the viola in a proper position. When you’re just starting, the angle should be at a 45-degree angle from the centerline. But you can adjust your position depending on your body frame and to whatever makes you comfortable in the long run.
When seated while playing, sit up straight on a steady chair. You may sit towards the front of the chair. You may tuck your right foot under your left foot sliding slightly forward or vice versa, depending which would make you more comfortable. A chair with a soft pad would be ideal to avoid lower back pain.
When standing, relax your knees and stand straight. If you feel comfortable, you can slide your left foot slightly forward.
The motion should be based on the base knuckle joint, and not on the finger joints. For the wrist, try to avoid a crooked position but make it in a neutral position instead to avoid tension. It is not advisable to rest your wrist on the ribcage of the instrument. While it’s good for practicing vibrato exercises, it's not advisable when playing the viola because it tends to make your wrist stuck in only one position.
If you notice that the tone and sound of your viola while being played are not clear, check for unnecessary tensions and make your movements as efficient as possible.
When playing the viola, make sure that the elbow is aligned depending on the chord you’ll be playing. If you’re playing on a G string, the elbow should swing to the right, and move toward the left when playing on an E string. Making sure that the elbow is moving as well will avoid tension on the fingers.
Pain should not be something that is associated with playing the viola, even during practice. If you feel pain or fatigue, then there’s something wrong. Check for muscle tension and postural imbalance. Lastly, always do exercises before practicing the viola.