Just out of interest what covers are you playing?
As said before (but just to mention it again): put your lead through your strap, nothing looks more stupid than someone bending over to put their lead back in
Think about what you want to hear on the monitor, and focus on that during rehearsals.
If your whole band does this, you can make a small rider out of it, to give to the soundtechs. This might help you get a better onstage sound. If you know the venue, you could also put up how you possibly might want to set the stage (which amp where, which monitor where). Mind however you are with 3 other bands, they might not want to switch too much.
But most important: have a great time on stage, try to interact with the other band members!