During wintertime, leave the instrument in the unopened case for a few moments coming in from the cold weather. Then open the case, and let it acclimatize to the room temperature. Then open the case and allow it to acclimatize for a few minutes before playing the instrument.
When you are not playing the instrument, always leave it in the case. This prevents accidents and evens out temperature and humidity changes.
Do not tighten the chinrest too much, because it can damage the ribs.
Do not leave the instrument (even when in the case) near radiators, in direct sunlight or close to other heat sources. This can potentially cause major damage to the instrument.
Wipe the rosin dust of the instrument carefully with a soft cotton cloth after every use. Remember to clean under the fingerboard and the tailpiece as well. Cotton or silk works well, do not use microfiber. Buy a new cloth at regular intervals.
Always wash your hands before touching the instrument.
Keep the pegs well lubricated. Use a special peg compound for this. Use special soap. Here is a video that shows how to fasten the strings correctly:
Avoid touching too much the varnished parts of the instrument. Think about how you hold it, even when there are long breaks in the orchestra.
Remember to store the shoulder rest safely in the case. Do not let any other objects like pencils, strings or rosin move around freely inside the case. This could potentially damage the instrument.
Keep an eye on the placement and angle of the bridge, especially when changing the strings. The strings should always be changed one at a time. Bring the instrument to a qualified violinmaker to check if you are unsure. See picture at the bottom of this page.
Use a very soft grade pencil in the grooves on the upper nut. This makes tuning easier.
Check the instrument regularly for cracks, open seams or other damage.
Be careful when using ”Damp-It” humidifier inside the instrument. I recommend the ”Stretto” humidifying system. If you keep the case closed, it is easier to maintain a “microclimate” and the right humidity in the case. Used only when the humidity is below 30%.
Check that the rubber feet of the shoulder rest are intact. Change the rubber if worn, to avoid damage to the edges of the instrument.