Use your gift before you feel ready. God rarely waits for the confident ones.

Readiness is not a qualification anybody checks. The people God used in the stories you know were mostly unsure, badly equipped and doing it anyway, which suggests confidence was never the entry requirement. Waiting until you feel competent means waiting for something that arrives through practice, and practice means starting underqualified.

Take the thing you can already do a bit of and use it this week at small scale. Play the song at the small service, teach the younger group, write the piece. Being visibly not ready is part of the process, not proof you should stop.