“I cut my students’ fingernails all the time,” says Hyeji Ahn, a violinist in Seoul, South Korea who has played and taught the violin for 23 years. In that time, Ahn has trimmed and shaped many musicians’ nails cut for playing string instruments. Use ordinary nail clippers. Remember that everyone’s hands and nails are shaped differently, so there’s no need to strictly adhere to the guidelines. Follow them, Ahn advises, but allow for a little flexibility.
With fingers used to press keyboards or strings, aim for a general shape where the skin protrudes more than the fingernails. “You need to use the skin directly under the nails to press the strings,” Ahn says, “so you don’t want long fingernails to bother you.” Cut the tips of your nails in a horizontal, nearly straight line.
For bow-holders, the thumbnail and pinky nail are the most important, since these fingers are used to hold and balance the bow across the strings. The thumb is tucked beneath the bow, with one edge of the thumbnail against the wood. Cut this edge into a vertical line rather than a curve to comfortably hold the bow. Because the pinky is curled to press down the bow with its fingertip, cut the pinky nail short, as you would your string fingernails. You want to avoid scraping the bow with your nail.
Trim your fingernails weekly so that they always maintain their shape. Having short and well-cut fingernails is necessary to maintain the ability to firmly press your strings and hold your bow, and being unhindered by long nails will also let you assume a correct hand, wrist, and arm position: all are factors that affect your sound quality, Ahn says. This is why, once her students decide to play their instrument professionally, she checks their fingernails before each lesson. “When you’re a musician, you have to account for many little details like that.”