Taya Smith presents 10 valuable aspects in worship leading. Among those ten things that she learned, she is clearly stating that your primary service to the church is to lead them to the presence of God. Among being yourself, taking any opportunity to learn, having others checking your song, and being balanced when you lead, preparation plays a massive role in worship leading.
Preparation is presented not only from a professional perspective but from a spiritual aspect that points toward spending time with God. For further information on worship, check out the Diploma in Christian Music Studies here.