You can use these instruments in ritual to represent and call the elements and to raise energy, you can use them outside of ritual to simply commune with the elements, or you can use them in spellwork or your choice.
Elemental Correspondences for Instruments:
Water is connected to resonant metals such as bells, chimes, cymbals, the triangle, the gong, the mbira, and the steel drum
Fire is connected to stringed instruments such as guitars, harps, the mandolin, the violin, the lyre, the hurdy gurdy, and the piano
Is connected to drums and contact instruments such as the xylophone, the marimba, maracas, and the tambourine
Air is connected to wind instruments such as the flute, the pan flute, the recorder, the clarinet, the oboe, the saxophone, the harmonica and the pianica,