Visit a music store and purchase a violin pick-up. If you wish, you can call ahead to confirm that the store has the part you need, though most music stores carry pick-ups as a standard part of inventory.
Clip or tape your violin pick-up to the body of the violin. Place it near the base of the violin or toward the side to produce the best sound.
String the cable around the violin and toward the amplifier. Make sure that the string does not interfere with your hands or fingers while you are playing the violin. Connect the pick-up cable to an amplifier.
Adjust the amplifier volume to the level you desire and play your violin. The pick-up will analyze the vibrations and electrify your violin.