It makes it much easier on the sound person if they know who is coming to gigs and what they will be playing. This way they can start to set up before you arrive if you are running late, so please make it known to other members whether you are coming or not. If you are one of the first to arrive at a gig, please communicate what you know to whoever needs to know.
Please help to set up microphones etc. It's common courtesy to do what you can to assist with the stage set up.