Prehearsal 101
If I told you there was a way to improve your musical and technical contribution to rehearsals and services by 100%, would you be interested? "Sure," you say? It's a little thing called prehearsal. In a nutshell, prehearsal is just preparing for the rehearsal. It's your personal prep time before rehearsal day. It's not rocket science, but it's effective.
A Challenge For Worship Leaders
Of course, this assumes you have access to Sunday's songs ahead of time, so a little challenge to the worship leaders among us: get those orders of worship to your teams ahead of time. My personal goal is to make OOWs (Orders Of Worship) available 10 days in advance (my team is snickering as they read this...).
Now, for all of us Spirit-led (and sometimes procrastinating) worship leaders - that doesn't mean it has to be set in stone. Sometimes plans will change, baptisms will get added to the service or the preacher may completely change directions on you. That's OK. But at least give your team the chance to prepare for rehearsal.
Prehearsal Precepts
With access to the upcoming OOW, team members can prehearse in a variety of ways so the first time they set eyes on the music isn't at the rehearsal:
1.  Listen to the songs
2.  Analyze the songs, if needed (see Listen And Learn)
3.  Review lead sheets, lyrics and performance notes
4.  Practice difficult passages, timings, and chord shapes
5.  Learn any new segues
6.  Memorize your parts
7.  Decide which keyboard or guitar patches to use on each song
8.  If you use loops, prep the loop
9.  Mentally walk through the service asking, "What must I do
     to make each part of this service flow smoothly into the next part?"
10. Read the Scripture references and sermon texts
11. Make note of any questions you need to ask
12. Finally, pray for the rehearsal
Tuning Into God
Implied in all of this is that you spend some time worshiping the Lord with the songs & readings for next Sunday. This is your personal "prayer closet", and it helps you make sure you not only perform the songs well, but that you worship the Lord through these songs.
The less you need to focus on fingerings, arrangements and technical details, the more thoughtful your contributions can be, and the more you can tune into God, even at rehearsal! When the others see you dining at the King's table, you won't be able to stop them from joining you at the feast!