Control your monitor mix. It’s important to know that the signal coming into your monitors does not need to be the same sound the audience is hearing through the mains. The auxiliary channels on your mixer allow you to hear a completely independent signal from the mains mix — and even to set effects (such as EQ) differently. The main thing is to ensure that you have clear rhythm and pitch references — and that your voice is set loud enough so that you don’t over sing to compensate for a weak vocal signal on stage. -from The Ultimate Guide to Singing