1. Connect a source to your StudioLive mixer and make sure the preamp volume is at a good volume input. Turn up the input fader and the Main L/R output fader on the Right hand side.
2. Click on the "Aux Inputs" tab and make sure that the Fader for the FX A Return is showing at Unity measure.
3. Click on the "FX A" tab under the "Main" tab. Turn up the output fader to unity, and slowly turn up the input to the FX bus. Make sure to listen for the FX level as you bring the fader up to a comfortable volume for the effect.
4. When you need to change the FX type (FX A-B are Reverb processors, FX C-D are Delay processors), you can click on the appropriate FX you want to edit, then click the FX Edit button on the Flex Fader for that FX Send.